tableam: Support for an index build's initial table scan(s).

To support building indexes over tables of different AMs, the scans to
do so need to be routed through the table AM.  While moving a fair
amount of code, nearly all the changes are just moving code to below a
callback.

Currently the range based interface wouldn't make much sense for non
block based table AMs. But that seems aceptable for now.

Author: Andres Freund
Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
This commit is contained in:
Andres Freund 2019-03-27 19:59:06 -07:00
parent 12bb35fc9b
commit 2a96909a4a
14 changed files with 1012 additions and 936 deletions

View File

@ -23,9 +23,9 @@
*/
#include "postgres.h"
#include "access/heapam.h"
#include "access/htup_details.h"
#include "access/nbtree.h"
#include "access/table.h"
#include "access/tableam.h"
#include "access/transam.h"
#include "access/xact.h"
@ -142,7 +142,7 @@ static void bt_tuple_present_callback(Relation index, HeapTuple htup,
Datum *values, bool *isnull,
bool tupleIsAlive, void *checkstate);
static IndexTuple bt_normalize_tuple(BtreeCheckState *state,
IndexTuple itup);
IndexTuple itup);
static bool bt_rootdescend(BtreeCheckState *state, IndexTuple itup);
static inline bool offset_is_negative_infinity(BTPageOpaque opaque,
OffsetNumber offset);
@ -387,10 +387,10 @@ bt_check_every_level(Relation rel, Relation heaprel, bool heapkeyspace,
/*
* Register our own snapshot in !readonly case, rather than asking
* IndexBuildHeapScan() to do this for us later. This needs to happen
* before index fingerprinting begins, so we can later be certain that
* index fingerprinting should have reached all tuples returned by
* IndexBuildHeapScan().
* table_index_build_scan() to do this for us later. This needs to
* happen before index fingerprinting begins, so we can later be
* certain that index fingerprinting should have reached all tuples
* returned by table_index_build_scan().
*
* In readonly case, we also check for problems with missing
* downlinks. A second Bloom filter is used for this.
@ -525,18 +525,19 @@ bt_check_every_level(Relation rel, Relation heaprel, bool heapkeyspace,
}
/*
* Create our own scan for IndexBuildHeapScan(), rather than getting
* it to do so for us. This is required so that we can actually use
* the MVCC snapshot registered earlier in !readonly case.
* Create our own scan for table_index_build_scan(), rather than
* getting it to do so for us. This is required so that we can
* actually use the MVCC snapshot registered earlier in !readonly
* case.
*
* Note that IndexBuildHeapScan() calls heap_endscan() for us.
* Note that table_index_build_scan() calls heap_endscan() for us.
*/
scan = table_beginscan_strat(state->heaprel, /* relation */
scan = table_beginscan_strat(state->heaprel, /* relation */
snapshot, /* snapshot */
0, /* number of keys */
0, /* number of keys */
NULL, /* scan key */
true, /* buffer access strategy OK */
true); /* syncscan OK? */
true); /* syncscan OK? */
/*
* Scan will behave as the first scan of a CREATE INDEX CONCURRENTLY
@ -565,8 +566,8 @@ bt_check_every_level(Relation rel, Relation heaprel, bool heapkeyspace,
RelationGetRelationName(state->rel),
RelationGetRelationName(state->heaprel));
IndexBuildHeapScan(state->heaprel, state->rel, indexinfo, true,
bt_tuple_present_callback, (void *) state, scan);
table_index_build_scan(state->heaprel, state->rel, indexinfo, true,
bt_tuple_present_callback, (void *) state, scan);
ereport(DEBUG1,
(errmsg_internal("finished verifying presence of " INT64_FORMAT " tuples from table \"%s\" with bitset %.2f%% set",
@ -814,7 +815,7 @@ nextpage:
* (Limited to heapallindexed readonly callers.)
*
* This is also where heapallindexed callers use their Bloom filter to
* fingerprint IndexTuples for later IndexBuildHeapScan() verification.
* fingerprint IndexTuples for later table_index_build_scan() verification.
*
* Note: Memory allocated in this routine is expected to be released by caller
* resetting state->targetcontext.
@ -1776,7 +1777,7 @@ bt_downlink_missing_check(BtreeCheckState *state)
}
/*
* Per-tuple callback from IndexBuildHeapScan, used to determine if index has
* Per-tuple callback from table_index_build_scan, used to determine if index has
* all the entries that definitely should have been observed in leaf pages of
* the target index (that is, all IndexTuples that were fingerprinted by our
* Bloom filter). All heapallindexed checks occur here.
@ -1801,7 +1802,7 @@ bt_downlink_missing_check(BtreeCheckState *state)
* verification, just in case it's a cross-page invariant issue, though that
* isn't particularly likely.
*
* IndexBuildHeapScan() expects to be able to find the root tuple when a
* table_index_build_scan() expects to be able to find the root tuple when a
* heap-only tuple (the live tuple at the end of some HOT chain) needs to be
* indexed, in order to replace the actual tuple's TID with the root tuple's
* TID (which is what we're actually passed back here). The index build heap
@ -1817,7 +1818,7 @@ bt_downlink_missing_check(BtreeCheckState *state)
* setting will probably also leave the index in a corrupt state before too
* long, the problem is nonetheless that there is heap corruption.)
*
* Heap-only tuple handling within IndexBuildHeapScan() works in a way that
* Heap-only tuple handling within table_index_build_scan() works in a way that
* helps us to detect index tuples that contain the wrong values (values that
* don't match the latest tuple in the HOT chain). This can happen when there
* is no superseding index tuple due to a faulty assessment of HOT safety,

View File

@ -14,6 +14,7 @@
#include "access/genam.h"
#include "access/generic_xlog.h"
#include "access/tableam.h"
#include "catalog/index.h"
#include "miscadmin.h"
#include "storage/bufmgr.h"
@ -69,7 +70,7 @@ initCachedPage(BloomBuildState *buildstate)
}
/*
* Per-tuple callback from IndexBuildHeapScan.
* Per-tuple callback for table_index_build_scan.
*/
static void
bloomBuildCallback(Relation index, HeapTuple htup, Datum *values,
@ -141,9 +142,9 @@ blbuild(Relation heap, Relation index, IndexInfo *indexInfo)
initCachedPage(&buildstate);
/* Do the heap scan */
reltuples = IndexBuildHeapScan(heap, index, indexInfo, true,
bloomBuildCallback, (void *) &buildstate,
NULL);
reltuples = table_index_build_scan(heap, index, indexInfo, true,
bloomBuildCallback, (void *) &buildstate,
NULL);
/* Flush last page if needed (it will be, unless heap was empty) */
if (buildstate.count > 0)

View File

@ -238,7 +238,7 @@ ambuild (Relation heapRelation,
but is empty. It must be filled in with whatever fixed data the
access method requires, plus entries for all tuples already existing
in the table. Ordinarily the <function>ambuild</function> function will call
<function>IndexBuildHeapScan()</function> to scan the table for existing tuples
<function>table_index_build_scan()</function> to scan the table for existing tuples
and compute the keys that need to be inserted into the index.
The function must return a palloc'd struct containing statistics about
the new index.

View File

@ -23,6 +23,7 @@
#include "access/reloptions.h"
#include "access/relscan.h"
#include "access/table.h"
#include "access/tableam.h"
#include "access/xloginsert.h"
#include "catalog/index.h"
#include "catalog/pg_am.h"
@ -587,7 +588,7 @@ brinendscan(IndexScanDesc scan)
}
/*
* Per-heap-tuple callback for IndexBuildHeapScan.
* Per-heap-tuple callback for table_index_build_scan.
*
* Note we don't worry about the page range at the end of the table here; it is
* present in the build state struct after we're called the last time, but not
@ -718,8 +719,8 @@ brinbuild(Relation heap, Relation index, IndexInfo *indexInfo)
* Now scan the relation. No syncscan allowed here because we want the
* heap blocks in physical order.
*/
reltuples = IndexBuildHeapScan(heap, index, indexInfo, false,
brinbuildCallback, (void *) state, NULL);
reltuples = table_index_build_scan(heap, index, indexInfo, false,
brinbuildCallback, (void *) state, NULL);
/* process the final batch */
form_and_insert_tuple(state);
@ -1230,13 +1231,14 @@ summarize_range(IndexInfo *indexInfo, BrinBuildState *state, Relation heapRel,
* short of brinbuildCallback creating the new index entry.
*
* Note that it is critical we use the "any visible" mode of
* IndexBuildHeapRangeScan here: otherwise, we would miss tuples inserted
* by transactions that are still in progress, among other corner cases.
* table_index_build_range_scan here: otherwise, we would miss tuples
* inserted by transactions that are still in progress, among other corner
* cases.
*/
state->bs_currRangeStart = heapBlk;
IndexBuildHeapRangeScan(heapRel, state->bs_irel, indexInfo, false, true,
heapBlk, scanNumBlks,
brinbuildCallback, (void *) state, NULL);
table_index_build_range_scan(heapRel, state->bs_irel, indexInfo, false, true,
heapBlk, scanNumBlks,
brinbuildCallback, (void *) state, NULL);
/*
* Now we update the values obtained by the scan with the placeholder

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@ -17,6 +17,7 @@
#include "access/gin_private.h"
#include "access/ginxlog.h"
#include "access/xloginsert.h"
#include "access/tableam.h"
#include "catalog/index.h"
#include "miscadmin.h"
#include "storage/bufmgr.h"
@ -394,8 +395,9 @@ ginbuild(Relation heap, Relation index, IndexInfo *indexInfo)
* Do the heap scan. We disallow sync scan here because dataPlaceToPage
* prefers to receive tuples in TID order.
*/
reltuples = IndexBuildHeapScan(heap, index, indexInfo, false,
ginBuildCallback, (void *) &buildstate, NULL);
reltuples = table_index_build_scan(heap, index, indexInfo, false,
ginBuildCallback, (void *) &buildstate,
NULL);
/* dump remaining entries to the index */
oldCtx = MemoryContextSwitchTo(buildstate.tmpCtx);

View File

@ -19,6 +19,7 @@
#include "access/genam.h"
#include "access/gist_private.h"
#include "access/gistxlog.h"
#include "access/tableam.h"
#include "access/xloginsert.h"
#include "catalog/index.h"
#include "miscadmin.h"
@ -204,8 +205,9 @@ gistbuild(Relation heap, Relation index, IndexInfo *indexInfo)
/*
* Do the heap scan.
*/
reltuples = IndexBuildHeapScan(heap, index, indexInfo, true,
gistBuildCallback, (void *) &buildstate, NULL);
reltuples = table_index_build_scan(heap, index, indexInfo, true,
gistBuildCallback,
(void *) &buildstate, NULL);
/*
* If buffering was used, flush out all the tuples that are still in the
@ -454,7 +456,7 @@ calculatePagesPerBuffer(GISTBuildState *buildstate, int levelStep)
}
/*
* Per-tuple callback from IndexBuildHeapScan.
* Per-tuple callback for table_index_build_scan.
*/
static void
gistBuildCallback(Relation index,

View File

@ -21,6 +21,7 @@
#include "access/hash.h"
#include "access/hash_xlog.h"
#include "access/relscan.h"
#include "access/tableam.h"
#include "catalog/index.h"
#include "commands/vacuum.h"
#include "miscadmin.h"
@ -159,8 +160,9 @@ hashbuild(Relation heap, Relation index, IndexInfo *indexInfo)
buildstate.heapRel = heap;
/* do the heap scan */
reltuples = IndexBuildHeapScan(heap, index, indexInfo, true,
hashbuildCallback, (void *) &buildstate, NULL);
reltuples = table_index_build_scan(heap, index, indexInfo, true,
hashbuildCallback,
(void *) &buildstate, NULL);
if (buildstate.spool)
{
@ -190,7 +192,7 @@ hashbuildempty(Relation index)
}
/*
* Per-tuple callback from IndexBuildHeapScan
* Per-tuple callback for table_index_build_scan
*/
static void
hashbuildCallback(Relation index,

View File

@ -19,11 +19,19 @@
*/
#include "postgres.h"
#include "miscadmin.h"
#include "access/genam.h"
#include "access/heapam.h"
#include "access/tableam.h"
#include "access/xact.h"
#include "catalog/catalog.h"
#include "catalog/index.h"
#include "executor/executor.h"
#include "storage/bufmgr.h"
#include "storage/bufpage.h"
#include "storage/lmgr.h"
#include "storage/procarray.h"
#include "utils/builtins.h"
@ -510,6 +518,744 @@ tuple_lock_retry:
}
/* ------------------------------------------------------------------------
* DDL related callbacks for heap AM.
* ------------------------------------------------------------------------
*/
static double
heapam_index_build_range_scan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
bool allow_sync,
bool anyvisible,
BlockNumber start_blockno,
BlockNumber numblocks,
IndexBuildCallback callback,
void *callback_state,
TableScanDesc scan)
{
HeapScanDesc hscan;
bool is_system_catalog;
bool checking_uniqueness;
HeapTuple heapTuple;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
double reltuples;
ExprState *predicate;
TupleTableSlot *slot;
EState *estate;
ExprContext *econtext;
Snapshot snapshot;
bool need_unregister_snapshot = false;
TransactionId OldestXmin;
BlockNumber root_blkno = InvalidBlockNumber;
OffsetNumber root_offsets[MaxHeapTuplesPerPage];
/*
* sanity checks
*/
Assert(OidIsValid(indexRelation->rd_rel->relam));
/* Remember if it's a system catalog */
is_system_catalog = IsSystemRelation(heapRelation);
/* See whether we're verifying uniqueness/exclusion properties */
checking_uniqueness = (indexInfo->ii_Unique ||
indexInfo->ii_ExclusionOps != NULL);
/*
* "Any visible" mode is not compatible with uniqueness checks; make sure
* only one of those is requested.
*/
Assert(!(anyvisible && checking_uniqueness));
/*
* Need an EState for evaluation of index expressions and partial-index
* predicates. Also a slot to hold the current tuple.
*/
estate = CreateExecutorState();
econtext = GetPerTupleExprContext(estate);
slot = table_slot_create(heapRelation, NULL);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Set up execution state for predicate, if any. */
predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
/*
* Prepare for scan of the base relation. In a normal index build, we use
* SnapshotAny because we must retrieve all tuples and do our own time
* qual checks (because we have to index RECENTLY_DEAD tuples). In a
* concurrent build, or during bootstrap, we take a regular MVCC snapshot
* and index whatever's live according to that.
*/
OldestXmin = InvalidTransactionId;
/* okay to ignore lazy VACUUMs here */
if (!IsBootstrapProcessingMode() && !indexInfo->ii_Concurrent)
OldestXmin = GetOldestXmin(heapRelation, PROCARRAY_FLAGS_VACUUM);
if (!scan)
{
/*
* Serial index build.
*
* Must begin our own heap scan in this case. We may also need to
* register a snapshot whose lifetime is under our direct control.
*/
if (!TransactionIdIsValid(OldestXmin))
{
snapshot = RegisterSnapshot(GetTransactionSnapshot());
need_unregister_snapshot = true;
}
else
snapshot = SnapshotAny;
scan = table_beginscan_strat(heapRelation, /* relation */
snapshot, /* snapshot */
0, /* number of keys */
NULL, /* scan key */
true, /* buffer access strategy OK */
allow_sync); /* syncscan OK? */
}
else
{
/*
* Parallel index build.
*
* Parallel case never registers/unregisters own snapshot. Snapshot
* is taken from parallel heap scan, and is SnapshotAny or an MVCC
* snapshot, based on same criteria as serial case.
*/
Assert(!IsBootstrapProcessingMode());
Assert(allow_sync);
snapshot = scan->rs_snapshot;
}
hscan = (HeapScanDesc) scan;
/*
* Must call GetOldestXmin() with SnapshotAny. Should never call
* GetOldestXmin() with MVCC snapshot. (It's especially worth checking
* this for parallel builds, since ambuild routines that support parallel
* builds must work these details out for themselves.)
*/
Assert(snapshot == SnapshotAny || IsMVCCSnapshot(snapshot));
Assert(snapshot == SnapshotAny ? TransactionIdIsValid(OldestXmin) :
!TransactionIdIsValid(OldestXmin));
Assert(snapshot == SnapshotAny || !anyvisible);
/* set our scan endpoints */
if (!allow_sync)
heap_setscanlimits(scan, start_blockno, numblocks);
else
{
/* syncscan can only be requested on whole relation */
Assert(start_blockno == 0);
Assert(numblocks == InvalidBlockNumber);
}
reltuples = 0;
/*
* Scan all tuples in the base relation.
*/
while ((heapTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
bool tupleIsAlive;
CHECK_FOR_INTERRUPTS();
/*
* When dealing with a HOT-chain of updated tuples, we want to index
* the values of the live tuple (if any), but index it under the TID
* of the chain's root tuple. This approach is necessary to preserve
* the HOT-chain structure in the heap. So we need to be able to find
* the root item offset for every tuple that's in a HOT-chain. When
* first reaching a new page of the relation, call
* heap_get_root_tuples() to build a map of root item offsets on the
* page.
*
* It might look unsafe to use this information across buffer
* lock/unlock. However, we hold ShareLock on the table so no
* ordinary insert/update/delete should occur; and we hold pin on the
* buffer continuously while visiting the page, so no pruning
* operation can occur either.
*
* Also, although our opinions about tuple liveness could change while
* we scan the page (due to concurrent transaction commits/aborts),
* the chain root locations won't, so this info doesn't need to be
* rebuilt after waiting for another transaction.
*
* Note the implied assumption that there is no more than one live
* tuple per HOT-chain --- else we could create more than one index
* entry pointing to the same root tuple.
*/
if (hscan->rs_cblock != root_blkno)
{
Page page = BufferGetPage(hscan->rs_cbuf);
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE);
heap_get_root_tuples(page, root_offsets);
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
root_blkno = hscan->rs_cblock;
}
if (snapshot == SnapshotAny)
{
/* do our own time qual check */
bool indexIt;
TransactionId xwait;
recheck:
/*
* We could possibly get away with not locking the buffer here,
* since caller should hold ShareLock on the relation, but let's
* be conservative about it. (This remark is still correct even
* with HOT-pruning: our pin on the buffer prevents pruning.)
*/
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE);
/*
* The criteria for counting a tuple as live in this block need to
* match what analyze.c's acquire_sample_rows() does, otherwise
* CREATE INDEX and ANALYZE may produce wildly different reltuples
* values, e.g. when there are many recently-dead tuples.
*/
switch (HeapTupleSatisfiesVacuum(heapTuple, OldestXmin,
hscan->rs_cbuf))
{
case HEAPTUPLE_DEAD:
/* Definitely dead, we can ignore it */
indexIt = false;
tupleIsAlive = false;
break;
case HEAPTUPLE_LIVE:
/* Normal case, index and unique-check it */
indexIt = true;
tupleIsAlive = true;
/* Count it as live, too */
reltuples += 1;
break;
case HEAPTUPLE_RECENTLY_DEAD:
/*
* If tuple is recently deleted then we must index it
* anyway to preserve MVCC semantics. (Pre-existing
* transactions could try to use the index after we finish
* building it, and may need to see such tuples.)
*
* However, if it was HOT-updated then we must only index
* the live tuple at the end of the HOT-chain. Since this
* breaks semantics for pre-existing snapshots, mark the
* index as unusable for them.
*
* We don't count recently-dead tuples in reltuples, even
* if we index them; see acquire_sample_rows().
*/
if (HeapTupleIsHotUpdated(heapTuple))
{
indexIt = false;
/* mark the index as unsafe for old snapshots */
indexInfo->ii_BrokenHotChain = true;
}
else
indexIt = true;
/* In any case, exclude the tuple from unique-checking */
tupleIsAlive = false;
break;
case HEAPTUPLE_INSERT_IN_PROGRESS:
/*
* In "anyvisible" mode, this tuple is visible and we
* don't need any further checks.
*/
if (anyvisible)
{
indexIt = true;
tupleIsAlive = true;
reltuples += 1;
break;
}
/*
* Since caller should hold ShareLock or better, normally
* the only way to see this is if it was inserted earlier
* in our own transaction. However, it can happen in
* system catalogs, since we tend to release write lock
* before commit there. Give a warning if neither case
* applies.
*/
xwait = HeapTupleHeaderGetXmin(heapTuple->t_data);
if (!TransactionIdIsCurrentTransactionId(xwait))
{
if (!is_system_catalog)
elog(WARNING, "concurrent insert in progress within table \"%s\"",
RelationGetRelationName(heapRelation));
/*
* If we are performing uniqueness checks, indexing
* such a tuple could lead to a bogus uniqueness
* failure. In that case we wait for the inserting
* transaction to finish and check again.
*/
if (checking_uniqueness)
{
/*
* Must drop the lock on the buffer before we wait
*/
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait, heapRelation,
&heapTuple->t_self,
XLTW_InsertIndexUnique);
CHECK_FOR_INTERRUPTS();
goto recheck;
}
}
else
{
/*
* For consistency with acquire_sample_rows(), count
* HEAPTUPLE_INSERT_IN_PROGRESS tuples as live only
* when inserted by our own transaction.
*/
reltuples += 1;
}
/*
* We must index such tuples, since if the index build
* commits then they're good.
*/
indexIt = true;
tupleIsAlive = true;
break;
case HEAPTUPLE_DELETE_IN_PROGRESS:
/*
* As with INSERT_IN_PROGRESS case, this is unexpected
* unless it's our own deletion or a system catalog; but
* in anyvisible mode, this tuple is visible.
*/
if (anyvisible)
{
indexIt = true;
tupleIsAlive = false;
reltuples += 1;
break;
}
xwait = HeapTupleHeaderGetUpdateXid(heapTuple->t_data);
if (!TransactionIdIsCurrentTransactionId(xwait))
{
if (!is_system_catalog)
elog(WARNING, "concurrent delete in progress within table \"%s\"",
RelationGetRelationName(heapRelation));
/*
* If we are performing uniqueness checks, assuming
* the tuple is dead could lead to missing a
* uniqueness violation. In that case we wait for the
* deleting transaction to finish and check again.
*
* Also, if it's a HOT-updated tuple, we should not
* index it but rather the live tuple at the end of
* the HOT-chain. However, the deleting transaction
* could abort, possibly leaving this tuple as live
* after all, in which case it has to be indexed. The
* only way to know what to do is to wait for the
* deleting transaction to finish and check again.
*/
if (checking_uniqueness ||
HeapTupleIsHotUpdated(heapTuple))
{
/*
* Must drop the lock on the buffer before we wait
*/
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait, heapRelation,
&heapTuple->t_self,
XLTW_InsertIndexUnique);
CHECK_FOR_INTERRUPTS();
goto recheck;
}
/*
* Otherwise index it but don't check for uniqueness,
* the same as a RECENTLY_DEAD tuple.
*/
indexIt = true;
/*
* Count HEAPTUPLE_DELETE_IN_PROGRESS tuples as live,
* if they were not deleted by the current
* transaction. That's what acquire_sample_rows()
* does, and we want the behavior to be consistent.
*/
reltuples += 1;
}
else if (HeapTupleIsHotUpdated(heapTuple))
{
/*
* It's a HOT-updated tuple deleted by our own xact.
* We can assume the deletion will commit (else the
* index contents don't matter), so treat the same as
* RECENTLY_DEAD HOT-updated tuples.
*/
indexIt = false;
/* mark the index as unsafe for old snapshots */
indexInfo->ii_BrokenHotChain = true;
}
else
{
/*
* It's a regular tuple deleted by our own xact. Index
* it, but don't check for uniqueness nor count in
* reltuples, the same as a RECENTLY_DEAD tuple.
*/
indexIt = true;
}
/* In any case, exclude the tuple from unique-checking */
tupleIsAlive = false;
break;
default:
elog(ERROR, "unexpected HeapTupleSatisfiesVacuum result");
indexIt = tupleIsAlive = false; /* keep compiler quiet */
break;
}
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
if (!indexIt)
continue;
}
else
{
/* heap_getnext did the time qual check */
tupleIsAlive = true;
reltuples += 1;
}
MemoryContextReset(econtext->ecxt_per_tuple_memory);
/* Set up for predicate or expression evaluation */
ExecStoreBufferHeapTuple(heapTuple, slot, hscan->rs_cbuf);
/*
* In a partial index, discard tuples that don't satisfy the
* predicate.
*/
if (predicate != NULL)
{
if (!ExecQual(predicate, econtext))
continue;
}
/*
* For the current heap tuple, extract all the attributes we use in
* this index, and note which are null. This also performs evaluation
* of any expressions needed.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
/*
* You'd think we should go ahead and build the index tuple here, but
* some index AMs want to do further processing on the data first. So
* pass the values[] and isnull[] arrays, instead.
*/
if (HeapTupleIsHeapOnly(heapTuple))
{
/*
* For a heap-only tuple, pretend its TID is that of the root. See
* src/backend/access/heap/README.HOT for discussion.
*/
HeapTupleData rootTuple;
OffsetNumber offnum;
rootTuple = *heapTuple;
offnum = ItemPointerGetOffsetNumber(&heapTuple->t_self);
if (!OffsetNumberIsValid(root_offsets[offnum - 1]))
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg_internal("failed to find parent tuple for heap-only tuple at (%u,%u) in table \"%s\"",
ItemPointerGetBlockNumber(&heapTuple->t_self),
offnum,
RelationGetRelationName(heapRelation))));
ItemPointerSetOffsetNumber(&rootTuple.t_self,
root_offsets[offnum - 1]);
/* Call the AM's callback routine to process the tuple */
callback(indexRelation, &rootTuple, values, isnull, tupleIsAlive,
callback_state);
}
else
{
/* Call the AM's callback routine to process the tuple */
callback(indexRelation, heapTuple, values, isnull, tupleIsAlive,
callback_state);
}
}
table_endscan(scan);
/* we can now forget our snapshot, if set and registered by us */
if (need_unregister_snapshot)
UnregisterSnapshot(snapshot);
ExecDropSingleTupleTableSlot(slot);
FreeExecutorState(estate);
/* These may have been pointing to the now-gone estate */
indexInfo->ii_ExpressionsState = NIL;
indexInfo->ii_PredicateState = NULL;
return reltuples;
}
static void
heapam_index_validate_scan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
Snapshot snapshot,
ValidateIndexState * state)
{
TableScanDesc scan;
HeapScanDesc hscan;
HeapTuple heapTuple;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
ExprState *predicate;
TupleTableSlot *slot;
EState *estate;
ExprContext *econtext;
BlockNumber root_blkno = InvalidBlockNumber;
OffsetNumber root_offsets[MaxHeapTuplesPerPage];
bool in_index[MaxHeapTuplesPerPage];
/* state variables for the merge */
ItemPointer indexcursor = NULL;
ItemPointerData decoded;
bool tuplesort_empty = false;
/*
* sanity checks
*/
Assert(OidIsValid(indexRelation->rd_rel->relam));
/*
* Need an EState for evaluation of index expressions and partial-index
* predicates. Also a slot to hold the current tuple.
*/
estate = CreateExecutorState();
econtext = GetPerTupleExprContext(estate);
slot = MakeSingleTupleTableSlot(RelationGetDescr(heapRelation),
&TTSOpsHeapTuple);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Set up execution state for predicate, if any. */
predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
/*
* Prepare for scan of the base relation. We need just those tuples
* satisfying the passed-in reference snapshot. We must disable syncscan
* here, because it's critical that we read from block zero forward to
* match the sorted TIDs.
*/
scan = table_beginscan_strat(heapRelation, /* relation */
snapshot, /* snapshot */
0, /* number of keys */
NULL, /* scan key */
true, /* buffer access strategy OK */
false); /* syncscan not OK */
hscan = (HeapScanDesc) scan;
/*
* Scan all tuples matching the snapshot.
*/
while ((heapTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
ItemPointer heapcursor = &heapTuple->t_self;
ItemPointerData rootTuple;
OffsetNumber root_offnum;
CHECK_FOR_INTERRUPTS();
state->htups += 1;
/*
* As commented in table_index_build_scan, we should index heap-only
* tuples under the TIDs of their root tuples; so when we advance onto
* a new heap page, build a map of root item offsets on the page.
*
* This complicates merging against the tuplesort output: we will
* visit the live tuples in order by their offsets, but the root
* offsets that we need to compare against the index contents might be
* ordered differently. So we might have to "look back" within the
* tuplesort output, but only within the current page. We handle that
* by keeping a bool array in_index[] showing all the
* already-passed-over tuplesort output TIDs of the current page. We
* clear that array here, when advancing onto a new heap page.
*/
if (hscan->rs_cblock != root_blkno)
{
Page page = BufferGetPage(hscan->rs_cbuf);
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE);
heap_get_root_tuples(page, root_offsets);
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
memset(in_index, 0, sizeof(in_index));
root_blkno = hscan->rs_cblock;
}
/* Convert actual tuple TID to root TID */
rootTuple = *heapcursor;
root_offnum = ItemPointerGetOffsetNumber(heapcursor);
if (HeapTupleIsHeapOnly(heapTuple))
{
root_offnum = root_offsets[root_offnum - 1];
if (!OffsetNumberIsValid(root_offnum))
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg_internal("failed to find parent tuple for heap-only tuple at (%u,%u) in table \"%s\"",
ItemPointerGetBlockNumber(heapcursor),
ItemPointerGetOffsetNumber(heapcursor),
RelationGetRelationName(heapRelation))));
ItemPointerSetOffsetNumber(&rootTuple, root_offnum);
}
/*
* "merge" by skipping through the index tuples until we find or pass
* the current root tuple.
*/
while (!tuplesort_empty &&
(!indexcursor ||
ItemPointerCompare(indexcursor, &rootTuple) < 0))
{
Datum ts_val;
bool ts_isnull;
if (indexcursor)
{
/*
* Remember index items seen earlier on the current heap page
*/
if (ItemPointerGetBlockNumber(indexcursor) == root_blkno)
in_index[ItemPointerGetOffsetNumber(indexcursor) - 1] = true;
}
tuplesort_empty = !tuplesort_getdatum(state->tuplesort, true,
&ts_val, &ts_isnull, NULL);
Assert(tuplesort_empty || !ts_isnull);
if (!tuplesort_empty)
{
itemptr_decode(&decoded, DatumGetInt64(ts_val));
indexcursor = &decoded;
/* If int8 is pass-by-ref, free (encoded) TID Datum memory */
#ifndef USE_FLOAT8_BYVAL
pfree(DatumGetPointer(ts_val));
#endif
}
else
{
/* Be tidy */
indexcursor = NULL;
}
}
/*
* If the tuplesort has overshot *and* we didn't see a match earlier,
* then this tuple is missing from the index, so insert it.
*/
if ((tuplesort_empty ||
ItemPointerCompare(indexcursor, &rootTuple) > 0) &&
!in_index[root_offnum - 1])
{
MemoryContextReset(econtext->ecxt_per_tuple_memory);
/* Set up for predicate or expression evaluation */
ExecStoreHeapTuple(heapTuple, slot, false);
/*
* In a partial index, discard tuples that don't satisfy the
* predicate.
*/
if (predicate != NULL)
{
if (!ExecQual(predicate, econtext))
continue;
}
/*
* For the current heap tuple, extract all the attributes we use
* in this index, and note which are null. This also performs
* evaluation of any expressions needed.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
/*
* You'd think we should go ahead and build the index tuple here,
* but some index AMs want to do further processing on the data
* first. So pass the values[] and isnull[] arrays, instead.
*/
/*
* If the tuple is already committed dead, you might think we
* could suppress uniqueness checking, but this is no longer true
* in the presence of HOT, because the insert is actually a proxy
* for a uniqueness check on the whole HOT-chain. That is, the
* tuple we have here could be dead because it was already
* HOT-updated, and if so the updating transaction will not have
* thought it should insert index entries. The index AM will
* check the whole HOT-chain and correctly detect a conflict if
* there is one.
*/
index_insert(indexRelation,
values,
isnull,
&rootTuple,
heapRelation,
indexInfo->ii_Unique ?
UNIQUE_CHECK_YES : UNIQUE_CHECK_NO,
indexInfo);
state->tups_inserted += 1;
}
}
table_endscan(scan);
ExecDropSingleTupleTableSlot(slot);
FreeExecutorState(estate);
/* These may have been pointing to the now-gone estate */
indexInfo->ii_ExpressionsState = NIL;
indexInfo->ii_PredicateState = NULL;
}
/* ------------------------------------------------------------------------
* Definition of the heap table access method.
* ------------------------------------------------------------------------
@ -545,6 +1291,9 @@ static const TableAmRoutine heapam_methods = {
.tuple_get_latest_tid = heap_get_latest_tid,
.tuple_satisfies_snapshot = heapam_tuple_satisfies_snapshot,
.compute_xid_horizon_for_tuples = heap_compute_xid_horizon_for_tuples,
.index_build_range_scan = heapam_index_build_range_scan,
.index_validate_scan = heapam_index_validate_scan,
};

View File

@ -480,9 +480,9 @@ _bt_spools_heapscan(Relation heap, Relation index, BTBuildState *buildstate,
/* Fill spool using either serial or parallel heap scan */
if (!buildstate->btleader)
reltuples = IndexBuildHeapScan(heap, index, indexInfo, true,
_bt_build_callback, (void *) buildstate,
NULL);
reltuples = table_index_build_scan(heap, index, indexInfo, true,
_bt_build_callback, (void *) buildstate,
NULL);
else
reltuples = _bt_parallel_heapscan(buildstate,
&indexInfo->ii_BrokenHotChain);
@ -558,7 +558,7 @@ _bt_leafbuild(BTSpool *btspool, BTSpool *btspool2)
}
/*
* Per-tuple callback from IndexBuildHeapScan
* Per-tuple callback for table_index_build_scan
*/
static void
_bt_build_callback(Relation index,
@ -1705,11 +1705,10 @@ _bt_parallel_scan_and_sort(BTSpool *btspool, BTSpool *btspool2,
/* Join parallel scan */
indexInfo = BuildIndexInfo(btspool->index);
indexInfo->ii_Concurrent = btshared->isconcurrent;
scan = table_beginscan_parallel(btspool->heap,
ParallelTableScanFromBTShared(btshared));
reltuples = IndexBuildHeapScan(btspool->heap, btspool->index, indexInfo,
true, _bt_build_callback,
(void *) &buildstate, scan);
scan = table_beginscan_parallel(btspool->heap, ParallelTableScanFromBTShared(btshared));
reltuples = table_index_build_scan(btspool->heap, btspool->index, indexInfo,
true, _bt_build_callback,
(void *) &buildstate, scan);
/*
* Execute this worker's part of the sort.

View File

@ -19,6 +19,7 @@
#include "access/genam.h"
#include "access/spgist_private.h"
#include "access/spgxlog.h"
#include "access/tableam.h"
#include "access/xlog.h"
#include "access/xloginsert.h"
#include "catalog/index.h"
@ -37,7 +38,7 @@ typedef struct
} SpGistBuildState;
/* Callback to process one heap tuple during IndexBuildHeapScan */
/* Callback to process one heap tuple during table_index_build_scan */
static void
spgistBuildCallback(Relation index, HeapTuple htup, Datum *values,
bool *isnull, bool tupleIsAlive, void *state)
@ -142,9 +143,9 @@ spgbuild(Relation heap, Relation index, IndexInfo *indexInfo)
"SP-GiST build temporary context",
ALLOCSET_DEFAULT_SIZES);
reltuples = IndexBuildHeapScan(heap, index, indexInfo, true,
spgistBuildCallback, (void *) &buildstate,
NULL);
reltuples = table_index_build_scan(heap, index, indexInfo, true,
spgistBuildCallback, (void *) &buildstate,
NULL);
MemoryContextDelete(buildstate.tmpCtx);

View File

@ -82,16 +82,6 @@
/* Potentially set by pg_upgrade_support functions */
Oid binary_upgrade_next_index_pg_class_oid = InvalidOid;
/* state info for validate_index bulkdelete callback */
typedef struct
{
Tuplesortstate *tuplesort; /* for sorting the index TIDs */
/* statistics (for debug purposes only): */
double htups,
itups,
tups_inserted;
} v_i_state;
/*
* Pointer-free representation of variables used when reindexing system
* catalogs; we use this to propagate those values to parallel workers.
@ -132,14 +122,7 @@ static void index_update_stats(Relation rel,
static void IndexCheckExclusion(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo);
static inline int64 itemptr_encode(ItemPointer itemptr);
static inline void itemptr_decode(ItemPointer itemptr, int64 encoded);
static bool validate_index_callback(ItemPointer itemptr, void *opaque);
static void validate_index_heapscan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
Snapshot snapshot,
v_i_state *state);
static bool ReindexIsCurrentlyProcessingIndex(Oid indexOid);
static void SetReindexProcessing(Oid heapOid, Oid indexOid);
static void ResetReindexProcessing(void);
@ -2397,557 +2380,6 @@ index_build(Relation heapRelation,
SetUserIdAndSecContext(save_userid, save_sec_context);
}
/*
* IndexBuildHeapScan - scan the heap relation to find tuples to be indexed
*
* This is called back from an access-method-specific index build procedure
* after the AM has done whatever setup it needs. The parent heap relation
* is scanned to find tuples that should be entered into the index. Each
* such tuple is passed to the AM's callback routine, which does the right
* things to add it to the new index. After we return, the AM's index
* build procedure does whatever cleanup it needs.
*
* The total count of live heap tuples is returned. This is for updating
* pg_class statistics. (It's annoying not to be able to do that here, but we
* want to merge that update with others; see index_update_stats.) Note that
* the index AM itself must keep track of the number of index tuples; we don't
* do so here because the AM might reject some of the tuples for its own
* reasons, such as being unable to store NULLs.
*
* A side effect is to set indexInfo->ii_BrokenHotChain to true if we detect
* any potentially broken HOT chains. Currently, we set this if there are
* any RECENTLY_DEAD or DELETE_IN_PROGRESS entries in a HOT chain, without
* trying very hard to detect whether they're really incompatible with the
* chain tip.
*/
double
IndexBuildHeapScan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
bool allow_sync,
IndexBuildCallback callback,
void *callback_state,
TableScanDesc scan)
{
return IndexBuildHeapRangeScan(heapRelation, indexRelation,
indexInfo, allow_sync,
false,
0, InvalidBlockNumber,
callback, callback_state, scan);
}
/*
* As above, except that instead of scanning the complete heap, only the given
* number of blocks are scanned. Scan to end-of-rel can be signalled by
* passing InvalidBlockNumber as numblocks. Note that restricting the range
* to scan cannot be done when requesting syncscan.
*
* When "anyvisible" mode is requested, all tuples visible to any transaction
* are indexed and counted as live, including those inserted or deleted by
* transactions that are still in progress.
*/
double
IndexBuildHeapRangeScan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
bool allow_sync,
bool anyvisible,
BlockNumber start_blockno,
BlockNumber numblocks,
IndexBuildCallback callback,
void *callback_state,
TableScanDesc scan)
{
HeapScanDesc hscan;
bool is_system_catalog;
bool checking_uniqueness;
HeapTuple heapTuple;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
double reltuples;
ExprState *predicate;
TupleTableSlot *slot;
EState *estate;
ExprContext *econtext;
Snapshot snapshot;
bool need_unregister_snapshot = false;
TransactionId OldestXmin;
BlockNumber root_blkno = InvalidBlockNumber;
OffsetNumber root_offsets[MaxHeapTuplesPerPage];
/*
* sanity checks
*/
Assert(OidIsValid(indexRelation->rd_rel->relam));
/* Remember if it's a system catalog */
is_system_catalog = IsSystemRelation(heapRelation);
/* See whether we're verifying uniqueness/exclusion properties */
checking_uniqueness = (indexInfo->ii_Unique ||
indexInfo->ii_ExclusionOps != NULL);
/*
* "Any visible" mode is not compatible with uniqueness checks; make sure
* only one of those is requested.
*/
Assert(!(anyvisible && checking_uniqueness));
/*
* Need an EState for evaluation of index expressions and partial-index
* predicates. Also a slot to hold the current tuple.
*/
estate = CreateExecutorState();
econtext = GetPerTupleExprContext(estate);
slot = table_slot_create(heapRelation, NULL);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Set up execution state for predicate, if any. */
predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
/*
* Prepare for scan of the base relation. In a normal index build, we use
* SnapshotAny because we must retrieve all tuples and do our own time
* qual checks (because we have to index RECENTLY_DEAD tuples). In a
* concurrent build, or during bootstrap, we take a regular MVCC snapshot
* and index whatever's live according to that.
*/
OldestXmin = InvalidTransactionId;
/* okay to ignore lazy VACUUMs here */
if (!IsBootstrapProcessingMode() && !indexInfo->ii_Concurrent)
OldestXmin = GetOldestXmin(heapRelation, PROCARRAY_FLAGS_VACUUM);
if (!scan)
{
/*
* Serial index build.
*
* Must begin our own heap scan in this case. We may also need to
* register a snapshot whose lifetime is under our direct control.
*/
if (!TransactionIdIsValid(OldestXmin))
{
snapshot = RegisterSnapshot(GetTransactionSnapshot());
need_unregister_snapshot = true;
}
else
snapshot = SnapshotAny;
scan = table_beginscan_strat(heapRelation, /* relation */
snapshot, /* snapshot */
0, /* number of keys */
NULL, /* scan key */
true, /* buffer access strategy OK */
allow_sync); /* syncscan OK? */
}
else
{
/*
* Parallel index build.
*
* Parallel case never registers/unregisters own snapshot. Snapshot
* is taken from parallel heap scan, and is SnapshotAny or an MVCC
* snapshot, based on same criteria as serial case.
*/
Assert(!IsBootstrapProcessingMode());
Assert(allow_sync);
snapshot = scan->rs_snapshot;
}
hscan = (HeapScanDesc) scan;
/*
* Must call GetOldestXmin() with SnapshotAny. Should never call
* GetOldestXmin() with MVCC snapshot. (It's especially worth checking
* this for parallel builds, since ambuild routines that support parallel
* builds must work these details out for themselves.)
*/
Assert(snapshot == SnapshotAny || IsMVCCSnapshot(snapshot));
Assert(snapshot == SnapshotAny ? TransactionIdIsValid(OldestXmin) :
!TransactionIdIsValid(OldestXmin));
Assert(snapshot == SnapshotAny || !anyvisible);
/* set our scan endpoints */
if (!allow_sync)
heap_setscanlimits(scan, start_blockno, numblocks);
else
{
/* syncscan can only be requested on whole relation */
Assert(start_blockno == 0);
Assert(numblocks == InvalidBlockNumber);
}
reltuples = 0;
/*
* Scan all tuples in the base relation.
*/
while ((heapTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
bool tupleIsAlive;
CHECK_FOR_INTERRUPTS();
/*
* When dealing with a HOT-chain of updated tuples, we want to index
* the values of the live tuple (if any), but index it under the TID
* of the chain's root tuple. This approach is necessary to preserve
* the HOT-chain structure in the heap. So we need to be able to find
* the root item offset for every tuple that's in a HOT-chain. When
* first reaching a new page of the relation, call
* heap_get_root_tuples() to build a map of root item offsets on the
* page.
*
* It might look unsafe to use this information across buffer
* lock/unlock. However, we hold ShareLock on the table so no
* ordinary insert/update/delete should occur; and we hold pin on the
* buffer continuously while visiting the page, so no pruning
* operation can occur either.
*
* Also, although our opinions about tuple liveness could change while
* we scan the page (due to concurrent transaction commits/aborts),
* the chain root locations won't, so this info doesn't need to be
* rebuilt after waiting for another transaction.
*
* Note the implied assumption that there is no more than one live
* tuple per HOT-chain --- else we could create more than one index
* entry pointing to the same root tuple.
*/
if (hscan->rs_cblock != root_blkno)
{
Page page = BufferGetPage(hscan->rs_cbuf);
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE);
heap_get_root_tuples(page, root_offsets);
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
root_blkno = hscan->rs_cblock;
}
if (snapshot == SnapshotAny)
{
/* do our own time qual check */
bool indexIt;
TransactionId xwait;
recheck:
/*
* We could possibly get away with not locking the buffer here,
* since caller should hold ShareLock on the relation, but let's
* be conservative about it. (This remark is still correct even
* with HOT-pruning: our pin on the buffer prevents pruning.)
*/
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE);
/*
* The criteria for counting a tuple as live in this block need to
* match what analyze.c's acquire_sample_rows() does, otherwise
* CREATE INDEX and ANALYZE may produce wildly different reltuples
* values, e.g. when there are many recently-dead tuples.
*/
switch (HeapTupleSatisfiesVacuum(heapTuple, OldestXmin,
hscan->rs_cbuf))
{
case HEAPTUPLE_DEAD:
/* Definitely dead, we can ignore it */
indexIt = false;
tupleIsAlive = false;
break;
case HEAPTUPLE_LIVE:
/* Normal case, index and unique-check it */
indexIt = true;
tupleIsAlive = true;
/* Count it as live, too */
reltuples += 1;
break;
case HEAPTUPLE_RECENTLY_DEAD:
/*
* If tuple is recently deleted then we must index it
* anyway to preserve MVCC semantics. (Pre-existing
* transactions could try to use the index after we finish
* building it, and may need to see such tuples.)
*
* However, if it was HOT-updated then we must only index
* the live tuple at the end of the HOT-chain. Since this
* breaks semantics for pre-existing snapshots, mark the
* index as unusable for them.
*
* We don't count recently-dead tuples in reltuples, even
* if we index them; see acquire_sample_rows().
*/
if (HeapTupleIsHotUpdated(heapTuple))
{
indexIt = false;
/* mark the index as unsafe for old snapshots */
indexInfo->ii_BrokenHotChain = true;
}
else
indexIt = true;
/* In any case, exclude the tuple from unique-checking */
tupleIsAlive = false;
break;
case HEAPTUPLE_INSERT_IN_PROGRESS:
/*
* In "anyvisible" mode, this tuple is visible and we
* don't need any further checks.
*/
if (anyvisible)
{
indexIt = true;
tupleIsAlive = true;
reltuples += 1;
break;
}
/*
* Since caller should hold ShareLock or better, normally
* the only way to see this is if it was inserted earlier
* in our own transaction. However, it can happen in
* system catalogs, since we tend to release write lock
* before commit there. Give a warning if neither case
* applies.
*/
xwait = HeapTupleHeaderGetXmin(heapTuple->t_data);
if (!TransactionIdIsCurrentTransactionId(xwait))
{
if (!is_system_catalog)
elog(WARNING, "concurrent insert in progress within table \"%s\"",
RelationGetRelationName(heapRelation));
/*
* If we are performing uniqueness checks, indexing
* such a tuple could lead to a bogus uniqueness
* failure. In that case we wait for the inserting
* transaction to finish and check again.
*/
if (checking_uniqueness)
{
/*
* Must drop the lock on the buffer before we wait
*/
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait, heapRelation,
&heapTuple->t_self,
XLTW_InsertIndexUnique);
CHECK_FOR_INTERRUPTS();
goto recheck;
}
}
else
{
/*
* For consistency with acquire_sample_rows(), count
* HEAPTUPLE_INSERT_IN_PROGRESS tuples as live only
* when inserted by our own transaction.
*/
reltuples += 1;
}
/*
* We must index such tuples, since if the index build
* commits then they're good.
*/
indexIt = true;
tupleIsAlive = true;
break;
case HEAPTUPLE_DELETE_IN_PROGRESS:
/*
* As with INSERT_IN_PROGRESS case, this is unexpected
* unless it's our own deletion or a system catalog; but
* in anyvisible mode, this tuple is visible.
*/
if (anyvisible)
{
indexIt = true;
tupleIsAlive = false;
reltuples += 1;
break;
}
xwait = HeapTupleHeaderGetUpdateXid(heapTuple->t_data);
if (!TransactionIdIsCurrentTransactionId(xwait))
{
if (!is_system_catalog)
elog(WARNING, "concurrent delete in progress within table \"%s\"",
RelationGetRelationName(heapRelation));
/*
* If we are performing uniqueness checks, assuming
* the tuple is dead could lead to missing a
* uniqueness violation. In that case we wait for the
* deleting transaction to finish and check again.
*
* Also, if it's a HOT-updated tuple, we should not
* index it but rather the live tuple at the end of
* the HOT-chain. However, the deleting transaction
* could abort, possibly leaving this tuple as live
* after all, in which case it has to be indexed. The
* only way to know what to do is to wait for the
* deleting transaction to finish and check again.
*/
if (checking_uniqueness ||
HeapTupleIsHotUpdated(heapTuple))
{
/*
* Must drop the lock on the buffer before we wait
*/
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait, heapRelation,
&heapTuple->t_self,
XLTW_InsertIndexUnique);
CHECK_FOR_INTERRUPTS();
goto recheck;
}
/*
* Otherwise index it but don't check for uniqueness,
* the same as a RECENTLY_DEAD tuple.
*/
indexIt = true;
/*
* Count HEAPTUPLE_DELETE_IN_PROGRESS tuples as live,
* if they were not deleted by the current
* transaction. That's what acquire_sample_rows()
* does, and we want the behavior to be consistent.
*/
reltuples += 1;
}
else if (HeapTupleIsHotUpdated(heapTuple))
{
/*
* It's a HOT-updated tuple deleted by our own xact.
* We can assume the deletion will commit (else the
* index contents don't matter), so treat the same as
* RECENTLY_DEAD HOT-updated tuples.
*/
indexIt = false;
/* mark the index as unsafe for old snapshots */
indexInfo->ii_BrokenHotChain = true;
}
else
{
/*
* It's a regular tuple deleted by our own xact. Index
* it, but don't check for uniqueness nor count in
* reltuples, the same as a RECENTLY_DEAD tuple.
*/
indexIt = true;
}
/* In any case, exclude the tuple from unique-checking */
tupleIsAlive = false;
break;
default:
elog(ERROR, "unexpected HeapTupleSatisfiesVacuum result");
indexIt = tupleIsAlive = false; /* keep compiler quiet */
break;
}
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
if (!indexIt)
continue;
}
else
{
/* heap_getnext did the time qual check */
tupleIsAlive = true;
reltuples += 1;
}
MemoryContextReset(econtext->ecxt_per_tuple_memory);
/* Set up for predicate or expression evaluation */
ExecStoreBufferHeapTuple(heapTuple, slot, hscan->rs_cbuf);
/*
* In a partial index, discard tuples that don't satisfy the
* predicate.
*/
if (predicate != NULL)
{
if (!ExecQual(predicate, econtext))
continue;
}
/*
* For the current heap tuple, extract all the attributes we use in
* this index, and note which are null. This also performs evaluation
* of any expressions needed.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
/*
* You'd think we should go ahead and build the index tuple here, but
* some index AMs want to do further processing on the data first. So
* pass the values[] and isnull[] arrays, instead.
*/
if (HeapTupleIsHeapOnly(heapTuple))
{
/*
* For a heap-only tuple, pretend its TID is that of the root. See
* src/backend/access/heap/README.HOT for discussion.
*/
HeapTupleData rootTuple;
OffsetNumber offnum;
rootTuple = *heapTuple;
offnum = ItemPointerGetOffsetNumber(&heapTuple->t_self);
if (!OffsetNumberIsValid(root_offsets[offnum - 1]))
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg_internal("failed to find parent tuple for heap-only tuple at (%u,%u) in table \"%s\"",
ItemPointerGetBlockNumber(&heapTuple->t_self),
offnum,
RelationGetRelationName(heapRelation))));
ItemPointerSetOffsetNumber(&rootTuple.t_self,
root_offsets[offnum - 1]);
/* Call the AM's callback routine to process the tuple */
callback(indexRelation, &rootTuple, values, isnull, tupleIsAlive,
callback_state);
}
else
{
/* Call the AM's callback routine to process the tuple */
callback(indexRelation, heapTuple, values, isnull, tupleIsAlive,
callback_state);
}
}
table_endscan(scan);
/* we can now forget our snapshot, if set and registered by us */
if (need_unregister_snapshot)
UnregisterSnapshot(snapshot);
ExecDropSingleTupleTableSlot(slot);
FreeExecutorState(estate);
/* These may have been pointing to the now-gone estate */
indexInfo->ii_ExpressionsState = NIL;
indexInfo->ii_PredicateState = NULL;
return reltuples;
}
/*
* IndexCheckExclusion - verify that a new exclusion constraint is satisfied
*
@ -3066,7 +2498,7 @@ IndexCheckExclusion(Relation heapRelation,
* incompatible HOT update done to it. We now build the index normally via
* index_build(), while holding a weak lock that allows concurrent
* insert/update/delete. Also, we index only tuples that are valid
* as of the start of the scan (see IndexBuildHeapScan), whereas a normal
* as of the start of the scan (see table_index_build_scan), whereas a normal
* build takes care to include recently-dead tuples. This is OK because
* we won't mark the index valid until all transactions that might be able
* to see those tuples are gone. The reason for doing that is to avoid
@ -3123,7 +2555,7 @@ validate_index(Oid heapId, Oid indexId, Snapshot snapshot)
indexRelation;
IndexInfo *indexInfo;
IndexVacuumInfo ivinfo;
v_i_state state;
ValidateIndexState state;
Oid save_userid;
int save_sec_context;
int save_nestlevel;
@ -3184,11 +2616,11 @@ validate_index(Oid heapId, Oid indexId, Snapshot snapshot)
/*
* Now scan the heap and "merge" it with the index
*/
validate_index_heapscan(heapRelation,
indexRelation,
indexInfo,
snapshot,
&state);
table_index_validate_scan(heapRelation,
indexRelation,
indexInfo,
snapshot,
&state);
/* Done with tuplesort object */
tuplesort_end(state.tuplesort);
@ -3208,53 +2640,13 @@ validate_index(Oid heapId, Oid indexId, Snapshot snapshot)
table_close(heapRelation, NoLock);
}
/*
* itemptr_encode - Encode ItemPointer as int64/int8
*
* This representation must produce values encoded as int64 that sort in the
* same order as their corresponding original TID values would (using the
* default int8 opclass to produce a result equivalent to the default TID
* opclass).
*
* As noted in validate_index(), this can be significantly faster.
*/
static inline int64
itemptr_encode(ItemPointer itemptr)
{
BlockNumber block = ItemPointerGetBlockNumber(itemptr);
OffsetNumber offset = ItemPointerGetOffsetNumber(itemptr);
int64 encoded;
/*
* Use the 16 least significant bits for the offset. 32 adjacent bits are
* used for the block number. Since remaining bits are unused, there
* cannot be negative encoded values (We assume a two's complement
* representation).
*/
encoded = ((uint64) block << 16) | (uint16) offset;
return encoded;
}
/*
* itemptr_decode - Decode int64/int8 representation back to ItemPointer
*/
static inline void
itemptr_decode(ItemPointer itemptr, int64 encoded)
{
BlockNumber block = (BlockNumber) (encoded >> 16);
OffsetNumber offset = (OffsetNumber) (encoded & 0xFFFF);
ItemPointerSet(itemptr, block, offset);
}
/*
* validate_index_callback - bulkdelete callback to collect the index TIDs
*/
static bool
validate_index_callback(ItemPointer itemptr, void *opaque)
{
v_i_state *state = (v_i_state *) opaque;
ValidateIndexState *state = (ValidateIndexState *) opaque;
int64 encoded = itemptr_encode(itemptr);
tuplesort_putdatum(state->tuplesort, Int64GetDatum(encoded), false);
@ -3262,245 +2654,6 @@ validate_index_callback(ItemPointer itemptr, void *opaque)
return false; /* never actually delete anything */
}
/*
* validate_index_heapscan - second table scan for concurrent index build
*
* This has much code in common with IndexBuildHeapScan, but it's enough
* different that it seems cleaner to have two routines not one.
*/
static void
validate_index_heapscan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
Snapshot snapshot,
v_i_state *state)
{
TableScanDesc scan;
HeapScanDesc hscan;
HeapTuple heapTuple;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
ExprState *predicate;
TupleTableSlot *slot;
EState *estate;
ExprContext *econtext;
BlockNumber root_blkno = InvalidBlockNumber;
OffsetNumber root_offsets[MaxHeapTuplesPerPage];
bool in_index[MaxHeapTuplesPerPage];
/* state variables for the merge */
ItemPointer indexcursor = NULL;
ItemPointerData decoded;
bool tuplesort_empty = false;
/*
* sanity checks
*/
Assert(OidIsValid(indexRelation->rd_rel->relam));
/*
* Need an EState for evaluation of index expressions and partial-index
* predicates. Also a slot to hold the current tuple.
*/
estate = CreateExecutorState();
econtext = GetPerTupleExprContext(estate);
slot = MakeSingleTupleTableSlot(RelationGetDescr(heapRelation),
&TTSOpsHeapTuple);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Set up execution state for predicate, if any. */
predicate = ExecPrepareQual(indexInfo->ii_Predicate, estate);
/*
* Prepare for scan of the base relation. We need just those tuples
* satisfying the passed-in reference snapshot. We must disable syncscan
* here, because it's critical that we read from block zero forward to
* match the sorted TIDs.
*/
scan = table_beginscan_strat(heapRelation, /* relation */
snapshot, /* snapshot */
0, /* number of keys */
NULL, /* scan key */
true, /* buffer access strategy OK */
false); /* syncscan not OK */
hscan = (HeapScanDesc) scan;
/*
* Scan all tuples matching the snapshot.
*/
while ((heapTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
ItemPointer heapcursor = &heapTuple->t_self;
ItemPointerData rootTuple;
OffsetNumber root_offnum;
CHECK_FOR_INTERRUPTS();
state->htups += 1;
/*
* As commented in IndexBuildHeapScan, we should index heap-only
* tuples under the TIDs of their root tuples; so when we advance onto
* a new heap page, build a map of root item offsets on the page.
*
* This complicates merging against the tuplesort output: we will
* visit the live tuples in order by their offsets, but the root
* offsets that we need to compare against the index contents might be
* ordered differently. So we might have to "look back" within the
* tuplesort output, but only within the current page. We handle that
* by keeping a bool array in_index[] showing all the
* already-passed-over tuplesort output TIDs of the current page. We
* clear that array here, when advancing onto a new heap page.
*/
if (hscan->rs_cblock != root_blkno)
{
Page page = BufferGetPage(hscan->rs_cbuf);
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE);
heap_get_root_tuples(page, root_offsets);
LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
memset(in_index, 0, sizeof(in_index));
root_blkno = hscan->rs_cblock;
}
/* Convert actual tuple TID to root TID */
rootTuple = *heapcursor;
root_offnum = ItemPointerGetOffsetNumber(heapcursor);
if (HeapTupleIsHeapOnly(heapTuple))
{
root_offnum = root_offsets[root_offnum - 1];
if (!OffsetNumberIsValid(root_offnum))
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg_internal("failed to find parent tuple for heap-only tuple at (%u,%u) in table \"%s\"",
ItemPointerGetBlockNumber(heapcursor),
ItemPointerGetOffsetNumber(heapcursor),
RelationGetRelationName(heapRelation))));
ItemPointerSetOffsetNumber(&rootTuple, root_offnum);
}
/*
* "merge" by skipping through the index tuples until we find or pass
* the current root tuple.
*/
while (!tuplesort_empty &&
(!indexcursor ||
ItemPointerCompare(indexcursor, &rootTuple) < 0))
{
Datum ts_val;
bool ts_isnull;
if (indexcursor)
{
/*
* Remember index items seen earlier on the current heap page
*/
if (ItemPointerGetBlockNumber(indexcursor) == root_blkno)
in_index[ItemPointerGetOffsetNumber(indexcursor) - 1] = true;
}
tuplesort_empty = !tuplesort_getdatum(state->tuplesort, true,
&ts_val, &ts_isnull, NULL);
Assert(tuplesort_empty || !ts_isnull);
if (!tuplesort_empty)
{
itemptr_decode(&decoded, DatumGetInt64(ts_val));
indexcursor = &decoded;
/* If int8 is pass-by-ref, free (encoded) TID Datum memory */
#ifndef USE_FLOAT8_BYVAL
pfree(DatumGetPointer(ts_val));
#endif
}
else
{
/* Be tidy */
indexcursor = NULL;
}
}
/*
* If the tuplesort has overshot *and* we didn't see a match earlier,
* then this tuple is missing from the index, so insert it.
*/
if ((tuplesort_empty ||
ItemPointerCompare(indexcursor, &rootTuple) > 0) &&
!in_index[root_offnum - 1])
{
MemoryContextReset(econtext->ecxt_per_tuple_memory);
/* Set up for predicate or expression evaluation */
ExecStoreHeapTuple(heapTuple, slot, false);
/*
* In a partial index, discard tuples that don't satisfy the
* predicate.
*/
if (predicate != NULL)
{
if (!ExecQual(predicate, econtext))
continue;
}
/*
* For the current heap tuple, extract all the attributes we use
* in this index, and note which are null. This also performs
* evaluation of any expressions needed.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
/*
* You'd think we should go ahead and build the index tuple here,
* but some index AMs want to do further processing on the data
* first. So pass the values[] and isnull[] arrays, instead.
*/
/*
* If the tuple is already committed dead, you might think we
* could suppress uniqueness checking, but this is no longer true
* in the presence of HOT, because the insert is actually a proxy
* for a uniqueness check on the whole HOT-chain. That is, the
* tuple we have here could be dead because it was already
* HOT-updated, and if so the updating transaction will not have
* thought it should insert index entries. The index AM will
* check the whole HOT-chain and correctly detect a conflict if
* there is one.
*/
index_insert(indexRelation,
values,
isnull,
&rootTuple,
heapRelation,
indexInfo->ii_Unique ?
UNIQUE_CHECK_YES : UNIQUE_CHECK_NO,
indexInfo);
state->tups_inserted += 1;
}
}
table_endscan(scan);
ExecDropSingleTupleTableSlot(slot);
FreeExecutorState(estate);
/* These may have been pointing to the now-gone estate */
indexInfo->ii_ExpressionsState = NIL;
indexInfo->ii_PredicateState = NULL;
}
/*
* index_set_state_flags - adjust pg_index state flags
*

View File

@ -28,6 +28,9 @@ extern bool synchronize_seqscans;
struct BulkInsertStateData;
struct IndexInfo;
struct IndexBuildCallback;
struct ValidateIndexState;
/*
@ -106,6 +109,14 @@ typedef struct TM_FailureData
#define TUPLE_LOCK_FLAG_FIND_LAST_VERSION (1 << 1)
/* Typedef for callback function for table_index_build_scan */
typedef void (*IndexBuildCallback) (Relation index,
HeapTuple htup,
Datum *values,
bool *isnull,
bool tupleIsAlive,
void *state);
/*
* API struct for a table AM. Note this must be allocated in a
* server-lifetime manner, typically as a static const struct, which then gets
@ -361,6 +372,31 @@ typedef struct TableAmRoutine
uint8 flags,
TM_FailureData *tmfd);
/* ------------------------------------------------------------------------
* DDL related functionality.
* ------------------------------------------------------------------------
*/
/* see table_index_build_range_scan for reference about parameters */
double (*index_build_range_scan) (Relation heap_rel,
Relation index_rel,
struct IndexInfo *index_nfo,
bool allow_sync,
bool anyvisible,
BlockNumber start_blockno,
BlockNumber end_blockno,
IndexBuildCallback callback,
void *callback_state,
TableScanDesc scan);
/* see table_index_validate_scan for reference about parameters */
void (*index_validate_scan) (Relation heap_rel,
Relation index_rel,
struct IndexInfo *index_info,
Snapshot snapshot,
struct ValidateIndexState *state);
} TableAmRoutine;
@ -920,6 +956,111 @@ table_lock_tuple(Relation rel, ItemPointer tid, Snapshot snapshot,
}
/* ------------------------------------------------------------------------
* DDL related functionality.
* ------------------------------------------------------------------------
*/
/*
* table_index_build_range_scan - scan the table to find tuples to be indexed
*
* This is called back from an access-method-specific index build procedure
* after the AM has done whatever setup it needs. The parent heap relation
* is scanned to find tuples that should be entered into the index. Each
* such tuple is passed to the AM's callback routine, which does the right
* things to add it to the new index. After we return, the AM's index
* build procedure does whatever cleanup it needs.
*
* The total count of live tuples is returned. This is for updating pg_class
* statistics. (It's annoying not to be able to do that here, but we want to
* merge that update with others; see index_update_stats.) Note that the
* index AM itself must keep track of the number of index tuples; we don't do
* so here because the AM might reject some of the tuples for its own reasons,
* such as being unable to store NULLs.
*
*
* A side effect is to set indexInfo->ii_BrokenHotChain to true if we detect
* any potentially broken HOT chains. Currently, we set this if there are any
* RECENTLY_DEAD or DELETE_IN_PROGRESS entries in a HOT chain, without trying
* very hard to detect whether they're really incompatible with the chain tip.
* This only really makes sense for heap AM, it might need to be generalized
* for other AMs later.
*/
static inline double
table_index_build_scan(Relation heap_rel,
Relation index_rel,
struct IndexInfo *index_nfo,
bool allow_sync,
IndexBuildCallback callback,
void *callback_state,
TableScanDesc scan)
{
return heap_rel->rd_tableam->index_build_range_scan(heap_rel,
index_rel,
index_nfo,
allow_sync,
false,
0,
InvalidBlockNumber,
callback,
callback_state,
scan);
}
/*
* As table_index_build_scan(), except that instead of scanning the complete
* table, only the given number of blocks are scanned. Scan to end-of-rel can
* be signalled by passing InvalidBlockNumber as numblocks. Note that
* restricting the range to scan cannot be done when requesting syncscan.
*
* When "anyvisible" mode is requested, all tuples visible to any transaction
* are indexed and counted as live, including those inserted or deleted by
* transactions that are still in progress.
*/
static inline double
table_index_build_range_scan(Relation heap_rel,
Relation index_rel,
struct IndexInfo *index_nfo,
bool allow_sync,
bool anyvisible,
BlockNumber start_blockno,
BlockNumber numblocks,
IndexBuildCallback callback,
void *callback_state,
TableScanDesc scan)
{
return heap_rel->rd_tableam->index_build_range_scan(heap_rel,
index_rel,
index_nfo,
allow_sync,
anyvisible,
start_blockno,
numblocks,
callback,
callback_state,
scan);
}
/*
* table_index_validate_scan - second table scan for concurrent index build
*
* See validate_index() for an explanation.
*/
static inline void
table_index_validate_scan(Relation heap_rel,
Relation index_rel,
struct IndexInfo *index_info,
Snapshot snapshot,
struct ValidateIndexState *state)
{
heap_rel->rd_tableam->index_validate_scan(heap_rel,
index_rel,
index_info,
snapshot,
state);
}
/* ----------------------------------------------------------------------------
* Functions to make modifications a bit simpler.
* ----------------------------------------------------------------------------

View File

@ -20,14 +20,6 @@
#define DEFAULT_INDEX_TYPE "btree"
/* Typedef for callback function for IndexBuildHeapScan */
typedef void (*IndexBuildCallback) (Relation index,
HeapTuple htup,
Datum *values,
bool *isnull,
bool tupleIsAlive,
void *state);
/* Action code for index_set_state_flags */
typedef enum
{
@ -37,6 +29,15 @@ typedef enum
INDEX_DROP_SET_DEAD
} IndexStateFlagsAction;
/* state info for validate_index bulkdelete callback */
typedef struct ValidateIndexState
{
Tuplesortstate *tuplesort; /* for sorting the index TIDs */
/* statistics (for debug purposes only): */
double htups,
itups,
tups_inserted;
} ValidateIndexState;
extern void index_check_primary_key(Relation heapRel,
IndexInfo *indexInfo,
@ -110,25 +111,6 @@ extern void index_build(Relation heapRelation,
bool isreindex,
bool parallel);
struct TableScanDescData;
extern double IndexBuildHeapScan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
bool allow_sync,
IndexBuildCallback callback,
void *callback_state,
struct TableScanDescData *scan);
extern double IndexBuildHeapRangeScan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
bool allow_sync,
bool anyvisible,
BlockNumber start_blockno,
BlockNumber end_blockno,
IndexBuildCallback callback,
void *callback_state,
struct TableScanDescData *scan);
extern void validate_index(Oid heapId, Oid indexId, Snapshot snapshot);
extern void index_set_state_flags(Oid indexId, IndexStateFlagsAction action);
@ -155,4 +137,45 @@ extern void RestoreReindexState(void *reindexstate);
extern void IndexSetParentIndex(Relation idx, Oid parentOid);
/*
* itemptr_encode - Encode ItemPointer as int64/int8
*
* This representation must produce values encoded as int64 that sort in the
* same order as their corresponding original TID values would (using the
* default int8 opclass to produce a result equivalent to the default TID
* opclass).
*
* As noted in validate_index(), this can be significantly faster.
*/
static inline int64
itemptr_encode(ItemPointer itemptr)
{
BlockNumber block = ItemPointerGetBlockNumber(itemptr);
OffsetNumber offset = ItemPointerGetOffsetNumber(itemptr);
int64 encoded;
/*
* Use the 16 least significant bits for the offset. 32 adjacent bits are
* used for the block number. Since remaining bits are unused, there
* cannot be negative encoded values (We assume a two's complement
* representation).
*/
encoded = ((uint64) block << 16) | (uint16) offset;
return encoded;
}
/*
* itemptr_decode - Decode int64/int8 representation back to ItemPointer
*/
static inline void
itemptr_decode(ItemPointer itemptr, int64 encoded)
{
BlockNumber block = (BlockNumber) (encoded >> 16);
OffsetNumber offset = (OffsetNumber) (encoded & 0xFFFF);
ItemPointerSet(itemptr, block, offset);
}
#endif /* INDEX_H */

View File

@ -2489,6 +2489,7 @@ VacAttrStatsP
VacuumParams
VacuumRelation
VacuumStmt
ValidateIndexState
Value
ValuesScan
ValuesScanState
@ -3239,7 +3240,6 @@ uuidKEY
uuid_rc_t
uuid_sortsupport_state
uuid_t
v_i_state
va_list
vacuumingOptions
validate_string_relopt