Move memory management away from writetup() and tuplesort_put*()

This commit puts some generic work away from sort-variant-specific function.
In particular, tuplesort_put*() now doesn't need to decrease available memory
and switch to sort context before calling puttuple_common().  writetup()
doesn't need to free SortTuple.tuple and increase available memory.

Discussion: https://postgr.es/m/CAPpHfdvjix0Ahx-H3Jp1M2R%2B_74P-zKnGGygx4OWr%3DbUQ8BNdw%40mail.gmail.com
Author: Alexander Korotkov
Reviewed-by: Pavel Borisov, Maxim Orlov, Matthias van de Meent
Reviewed-by: Andres Freund, John Naylor
This commit is contained in:
Alexander Korotkov 2022-07-27 08:27:58 +03:00
parent 033dd02db2
commit 097366c45f

View File

@ -288,11 +288,7 @@ struct Tuplesortstate
/*
* Function to write a stored tuple onto tape. The representation of the
* tuple on tape need not be the same as it is in memory; requirements on
* the tape representation are given below. Unless the slab allocator is
* used, after writing the tuple, pfree() the out-of-line data (not the
* SortTuple struct!), and increase state->availMem by the amount of
* memory space thereby released.
* tuple on tape need not be the same as it is in memory.
*/
void (*writetup) (Tuplesortstate *state, LogicalTape *tape,
SortTuple *stup);
@ -549,7 +545,7 @@ struct Sharedsort
#define REMOVEABBREV(state,stup,count) ((*(state)->removeabbrev) (state, stup, count))
#define COMPARETUP(state,a,b) ((*(state)->comparetup) (a, b, state))
#define WRITETUP(state,tape,stup) ((*(state)->writetup) (state, tape, stup))
#define WRITETUP(state,tape,stup) (writetuple(state, tape, stup))
#define READTUP(state,stup,tape,len) ((*(state)->readtup) (state, stup, tape, len))
#define LACKMEM(state) ((state)->availMem < 0 && !(state)->slabAllocatorUsed)
#define USEMEM(state,amt) ((state)->availMem -= (amt))
@ -618,6 +614,8 @@ static Tuplesortstate *tuplesort_begin_common(int workMem,
static void tuplesort_begin_batch(Tuplesortstate *state);
static void puttuple_common(Tuplesortstate *state, SortTuple *tuple,
bool useAbbrev);
static void writetuple(Tuplesortstate *state, LogicalTape *tape,
SortTuple *stup);
static bool consider_abort_common(Tuplesortstate *state);
static void inittapes(Tuplesortstate *state, bool mergeruns);
static void inittapestate(Tuplesortstate *state, int maxTapes);
@ -1848,7 +1846,6 @@ tuplesort_puttupleslot(Tuplesortstate *state, TupleTableSlot *slot)
/* copy the tuple into sort storage */
tuple = ExecCopySlotMinimalTuple(slot);
stup.tuple = (void *) tuple;
USEMEM(state, GetMemoryChunkSpace(tuple));
/* set up first-column key value */
htup.t_len = tuple->t_len + MINIMAL_TUPLE_OFFSET;
htup.t_data = (HeapTupleHeader) ((char *) tuple - MINIMAL_TUPLE_OFFSET);
@ -1857,8 +1854,6 @@ tuplesort_puttupleslot(Tuplesortstate *state, TupleTableSlot *slot)
state->tupDesc,
&stup.isnull1);
MemoryContextSwitchTo(state->sortcontext);
puttuple_common(state, &stup,
state->sortKeys->abbrev_converter && !stup.isnull1);
@ -1879,9 +1874,6 @@ tuplesort_putheaptuple(Tuplesortstate *state, HeapTuple tup)
/* copy the tuple into sort storage */
tup = heap_copytuple(tup);
stup.tuple = (void *) tup;
USEMEM(state, GetMemoryChunkSpace(tup));
MemoryContextSwitchTo(state->sortcontext);
/*
* set up first-column key value, and potentially abbreviate, if it's a
@ -1910,7 +1902,6 @@ tuplesort_putindextuplevalues(Tuplesortstate *state, Relation rel,
ItemPointer self, Datum *values,
bool *isnull)
{
MemoryContext oldcontext;
SortTuple stup;
IndexTuple tuple;
@ -1918,19 +1909,14 @@ tuplesort_putindextuplevalues(Tuplesortstate *state, Relation rel,
isnull, state->tuplecontext);
tuple = ((IndexTuple) stup.tuple);
tuple->t_tid = *self;
USEMEM(state, GetMemoryChunkSpace(stup.tuple));
/* set up first-column key value */
stup.datum1 = index_getattr(tuple,
1,
RelationGetDescr(state->indexRel),
&stup.isnull1);
oldcontext = MemoryContextSwitchTo(state->sortcontext);
puttuple_common(state, &stup,
state->sortKeys && state->sortKeys->abbrev_converter && !stup.isnull1);
MemoryContextSwitchTo(oldcontext);
}
/*
@ -1965,15 +1951,12 @@ tuplesort_putdatum(Tuplesortstate *state, Datum val, bool isNull)
stup.datum1 = !isNull ? val : (Datum) 0;
stup.isnull1 = isNull;
stup.tuple = NULL; /* no separate storage */
MemoryContextSwitchTo(state->sortcontext);
}
else
{
stup.isnull1 = false;
stup.datum1 = datumCopy(val, false, state->datumTypeLen);
stup.tuple = DatumGetPointer(stup.datum1);
USEMEM(state, GetMemoryChunkSpace(stup.tuple));
MemoryContextSwitchTo(state->sortcontext);
}
puttuple_common(state, &stup,
@ -1988,8 +1971,14 @@ tuplesort_putdatum(Tuplesortstate *state, Datum val, bool isNull)
static void
puttuple_common(Tuplesortstate *state, SortTuple *tuple, bool useAbbrev)
{
MemoryContext oldcontext = MemoryContextSwitchTo(state->sortcontext);
Assert(!LEADER(state));
/* Count the size of the out-of-line data */
if (tuple->tuple != NULL)
USEMEM(state, GetMemoryChunkSpace(tuple->tuple));
if (!useAbbrev)
{
/*
@ -2062,6 +2051,7 @@ puttuple_common(Tuplesortstate *state, SortTuple *tuple, bool useAbbrev)
pg_rusage_show(&state->ru_start));
#endif
make_bounded_heap(state);
MemoryContextSwitchTo(oldcontext);
return;
}
@ -2069,7 +2059,10 @@ puttuple_common(Tuplesortstate *state, SortTuple *tuple, bool useAbbrev)
* Done if we still fit in available memory and have array slots.
*/
if (state->memtupcount < state->memtupsize && !LACKMEM(state))
{
MemoryContextSwitchTo(oldcontext);
return;
}
/*
* Nope; time to switch to tape-based operation.
@ -2123,6 +2116,25 @@ puttuple_common(Tuplesortstate *state, SortTuple *tuple, bool useAbbrev)
elog(ERROR, "invalid tuplesort state");
break;
}
MemoryContextSwitchTo(oldcontext);
}
/*
* Write a stored tuple onto tape.tuple. Unless the slab allocator is
* used, after writing the tuple, pfree() the out-of-line data (not the
* SortTuple struct!), and increase state->availMem by the amount of
* memory space thereby released.
*/
static void
writetuple(Tuplesortstate *state, LogicalTape *tape, SortTuple *stup)
{
state->writetup(state, tape, stup);
if (!state->slabAllocatorUsed && stup->tuple)
{
FREEMEM(state, GetMemoryChunkSpace(stup->tuple));
pfree(stup->tuple);
}
}
static bool
@ -3960,12 +3972,6 @@ writetup_heap(Tuplesortstate *state, LogicalTape *tape, SortTuple *stup)
if (state->sortopt & TUPLESORT_RANDOMACCESS) /* need trailing length
* word? */
LogicalTapeWrite(tape, (void *) &tuplen, sizeof(tuplen));
if (!state->slabAllocatorUsed)
{
FREEMEM(state, GetMemoryChunkSpace(tuple));
heap_free_minimal_tuple(tuple);
}
}
static void
@ -4141,12 +4147,6 @@ writetup_cluster(Tuplesortstate *state, LogicalTape *tape, SortTuple *stup)
if (state->sortopt & TUPLESORT_RANDOMACCESS) /* need trailing length
* word? */
LogicalTapeWrite(tape, &tuplen, sizeof(tuplen));
if (!state->slabAllocatorUsed)
{
FREEMEM(state, GetMemoryChunkSpace(tuple));
heap_freetuple(tuple);
}
}
static void
@ -4403,12 +4403,6 @@ writetup_index(Tuplesortstate *state, LogicalTape *tape, SortTuple *stup)
if (state->sortopt & TUPLESORT_RANDOMACCESS) /* need trailing length
* word? */
LogicalTapeWrite(tape, (void *) &tuplen, sizeof(tuplen));
if (!state->slabAllocatorUsed)
{
FREEMEM(state, GetMemoryChunkSpace(tuple));
pfree(tuple);
}
}
static void
@ -4495,12 +4489,6 @@ writetup_datum(Tuplesortstate *state, LogicalTape *tape, SortTuple *stup)
if (state->sortopt & TUPLESORT_RANDOMACCESS) /* need trailing length
* word? */
LogicalTapeWrite(tape, (void *) &writtenlen, sizeof(writtenlen));
if (!state->slabAllocatorUsed && stup->tuple)
{
FREEMEM(state, GetMemoryChunkSpace(stup->tuple));
pfree(stup->tuple);
}
}
static void