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Install a "dead man switch" to allow the postmaster to detect cases where
a backend has done exit(0) or exit(1) without having disengaged itself from shared memory. We are at risk for this whenever third-party code is loaded into a backend, since such code might not know it's supposed to go through proc_exit() instead. Also, it is reported that under Windows there are ways to externally kill a process that cause the status code returned to the postmaster to be indistinguishable from a voluntary exit (thank you, Microsoft). If this does happen then the system is probably hosed --- for instance, the dead session might still be holding locks. So the best recovery method is to treat this like a backend crash. The dead man switch is armed for a particular child process when it acquires a regular PGPROC, and disarmed when the PGPROC is released; these should be the first and last touches of shared memory resources in a backend, or close enough anyway. This choice means there is no coverage for auxiliary processes, but I doubt we need that, since they shouldn't be executing any user-provided code anyway. This patch also improves the management of the EXEC_BACKEND ShmemBackendArray array a bit, by reducing search costs. Although this problem is of long standing, the lack of field complaints seems to mean it's not critical enough to risk back-patching; at least not till we get some more testing of this mechanism.
This commit is contained in:
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8f348112f3
commit
969d7cd431
@ -37,7 +37,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/postmaster/postmaster.c,v 1.580 2009/05/04 02:46:36 tgl Exp $
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* $PostgreSQL: pgsql/src/backend/postmaster/postmaster.c,v 1.581 2009/05/05 19:59:00 tgl Exp $
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*
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* NOTES
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*
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@ -135,12 +135,14 @@
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* Also, "dead_end" children are in it: these are children launched just
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* for the purpose of sending a friendly rejection message to a would-be
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* client. We must track them because they are attached to shared memory,
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* but we know they will never become live backends.
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* but we know they will never become live backends. dead_end children are
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* not assigned a PMChildSlot.
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*/
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typedef struct bkend
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{
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pid_t pid; /* process id of backend */
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long cancel_key; /* cancel key for cancels for this backend */
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int child_slot; /* PMChildSlot for this backend, if any */
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bool is_autovacuum; /* is it an autovacuum process? */
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bool dead_end; /* is it going to send an error and quit? */
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Dlelem elem; /* list link in BackendList */
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@ -149,15 +151,6 @@ typedef struct bkend
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static Dllist *BackendList;
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#ifdef EXEC_BACKEND
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/*
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* Number of entries in the shared-memory backend table. This table is used
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* only for sending cancels, and therefore only includes children we allow
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* cancels on: regular backends and autovac workers. In particular we exclude
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* dead_end children, allowing the table to have a known maximum size, to wit
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* the same too-many-children limit enforced by canAcceptConnections().
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*/
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#define NUM_BACKENDARRAY_ELEMS (2*MaxBackends)
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static Backend *ShmemBackendArray;
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#endif
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@ -404,6 +397,7 @@ typedef struct
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char DataDir[MAXPGPATH];
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int ListenSocket[MAXLISTEN];
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long MyCancelKey;
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int MyPMChildSlot;
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unsigned long UsedShmemSegID;
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void *UsedShmemSegAddr;
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slock_t *ShmemLock;
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@ -413,6 +407,7 @@ typedef struct
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slock_t *ProcStructLock;
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PROC_HDR *ProcGlobal;
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PGPROC *AuxiliaryProcs;
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PMSignalData *PMSignalState;
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InheritableSocket pgStatSock;
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pid_t PostmasterPid;
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TimestampTz PgStartTime;
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@ -443,7 +438,7 @@ static bool save_backend_variables(BackendParameters * param, Port *port,
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#endif
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static void ShmemBackendArrayAdd(Backend *bn);
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static void ShmemBackendArrayRemove(pid_t pid);
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static void ShmemBackendArrayRemove(Backend *bn);
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#endif /* EXEC_BACKEND */
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#define StartupDataBase() StartChildProcess(StartupProcess)
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@ -1771,7 +1766,7 @@ processCancelRequest(Port *port, void *pkt)
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{
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bp = (Backend *) DLE_VAL(curr);
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#else
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for (i = 0; i < NUM_BACKENDARRAY_ELEMS; i++)
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for (i = MaxLivePostmasterChildren() - 1; i >= 0; i--)
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{
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bp = (Backend *) &ShmemBackendArray[i];
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#endif
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@ -1836,10 +1831,10 @@ canAcceptConnections(void)
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* MaxBackends limit is enforced when a new backend tries to join the
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* shared-inval backend array.
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*
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* In the EXEC_BACKEND case, the limit here must match the size of the
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* ShmemBackendArray, since all these processes will have cancel codes.
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* The limit here must match the sizes of the per-child-process arrays;
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* see comments for MaxLivePostmasterChildren().
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*/
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if (CountChildren() >= 2 * MaxBackends)
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if (CountChildren() >= MaxLivePostmasterChildren())
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return CAC_TOOMANY;
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return CAC_OK;
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@ -2439,8 +2434,8 @@ CleanupBackend(int pid,
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/*
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* If a backend dies in an ugly way then we must signal all other backends
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* to quickdie. If exit status is zero (normal) or one (FATAL exit), we
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* assume everything is all right and simply remove the backend from the
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* active backend list.
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* assume everything is all right and proceed to remove the backend from
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* the active backend list.
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*/
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if (!EXIT_STATUS_0(exitstatus) && !EXIT_STATUS_1(exitstatus))
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{
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@ -2454,10 +2449,21 @@ CleanupBackend(int pid,
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if (bp->pid == pid)
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{
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#ifdef EXEC_BACKEND
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if (!bp->dead_end)
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ShmemBackendArrayRemove(pid);
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{
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if (!ReleasePostmasterChildSlot(bp->child_slot))
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{
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/*
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* Uh-oh, the child failed to clean itself up. Treat
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* as a crash after all.
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*/
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HandleChildCrash(pid, exitstatus, _("server process"));
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return;
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}
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#ifdef EXEC_BACKEND
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ShmemBackendArrayRemove(bp);
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#endif
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}
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DLRemove(curr);
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free(bp);
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break;
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@ -2500,10 +2506,13 @@ HandleChildCrash(int pid, int exitstatus, const char *procname)
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/*
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* Found entry for freshly-dead backend, so remove it.
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*/
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#ifdef EXEC_BACKEND
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if (!bp->dead_end)
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ShmemBackendArrayRemove(pid);
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{
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(void) ReleasePostmasterChildSlot(bp->child_slot);
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#ifdef EXEC_BACKEND
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ShmemBackendArrayRemove(bp);
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#endif
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}
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DLRemove(curr);
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free(bp);
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/* Keep looping so we can signal remaining backends */
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@ -2931,14 +2940,7 @@ BackendStartup(Port *port)
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pid_t pid;
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/*
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* Compute the cancel key that will be assigned to this backend. The
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* backend will have its own copy in the forked-off process' value of
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* MyCancelKey, so that it can transmit the key to the frontend.
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*/
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MyCancelKey = PostmasterRandom();
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/*
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* Make room for backend data structure. Better before the fork() so we
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* Create backend data structure. Better before the fork() so we
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* can handle failure cleanly.
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*/
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bn = (Backend *) malloc(sizeof(Backend));
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@ -2950,8 +2952,26 @@ BackendStartup(Port *port)
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return STATUS_ERROR;
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}
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/*
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* Compute the cancel key that will be assigned to this backend. The
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* backend will have its own copy in the forked-off process' value of
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* MyCancelKey, so that it can transmit the key to the frontend.
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*/
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MyCancelKey = PostmasterRandom();
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bn->cancel_key = MyCancelKey;
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/* Pass down canAcceptConnections state */
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port->canAcceptConnections = canAcceptConnections();
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bn->dead_end = (port->canAcceptConnections != CAC_OK &&
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port->canAcceptConnections != CAC_WAITBACKUP);
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/*
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* Unless it's a dead_end child, assign it a child slot number
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*/
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if (!bn->dead_end)
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bn->child_slot = MyPMChildSlot = AssignPostmasterChildSlot();
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else
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bn->child_slot = 0;
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#ifdef EXEC_BACKEND
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pid = backend_forkexec(port);
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@ -3009,10 +3029,7 @@ BackendStartup(Port *port)
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* of backends.
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*/
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bn->pid = pid;
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bn->cancel_key = MyCancelKey;
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bn->is_autovacuum = false;
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bn->dead_end = (port->canAcceptConnections != CAC_OK &&
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port->canAcceptConnections != CAC_WAITBACKUP);
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DLInitElem(&bn->elem, bn);
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DLAddHead(BackendList, &bn->elem);
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#ifdef EXEC_BACKEND
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@ -4271,23 +4288,26 @@ StartAutovacuumWorker(void)
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*/
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if (canAcceptConnections() == CAC_OK)
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{
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/*
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* Compute the cancel key that will be assigned to this session. We
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* probably don't need cancel keys for autovac workers, but we'd
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* better have something random in the field to prevent unfriendly
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* people from sending cancels to them.
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*/
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MyCancelKey = PostmasterRandom();
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bn = (Backend *) malloc(sizeof(Backend));
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if (bn)
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{
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/*
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* Compute the cancel key that will be assigned to this session. We
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* probably don't need cancel keys for autovac workers, but we'd
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* better have something random in the field to prevent unfriendly
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* people from sending cancels to them.
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*/
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MyCancelKey = PostmasterRandom();
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bn->cancel_key = MyCancelKey;
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/* Autovac workers are not dead_end and need a child slot */
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bn->dead_end = false;
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bn->child_slot = MyPMChildSlot = AssignPostmasterChildSlot();
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bn->pid = StartAutoVacWorker();
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if (bn->pid > 0)
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{
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bn->cancel_key = MyCancelKey;
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bn->is_autovacuum = true;
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bn->dead_end = false;
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DLInitElem(&bn->elem, bn);
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DLAddHead(BackendList, &bn->elem);
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#ifdef EXEC_BACKEND
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@ -4353,6 +4373,24 @@ CreateOptsFile(int argc, char *argv[], char *fullprogname)
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}
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/*
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* MaxLivePostmasterChildren
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*
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* This reports the number of entries needed in per-child-process arrays
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* (the PMChildFlags array, and if EXEC_BACKEND the ShmemBackendArray).
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* These arrays include regular backends and autovac workers, but not special
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* children nor dead_end children. This allows the arrays to have a fixed
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* maximum size, to wit the same too-many-children limit enforced by
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* canAcceptConnections(). The exact value isn't too critical as long as
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* it's more than MaxBackends.
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*/
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int
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MaxLivePostmasterChildren(void)
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{
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return 2 * MaxBackends;
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}
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#ifdef EXEC_BACKEND
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/*
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@ -4364,6 +4402,7 @@ extern LWLock *LWLockArray;
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extern slock_t *ProcStructLock;
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extern PROC_HDR *ProcGlobal;
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extern PGPROC *AuxiliaryProcs;
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extern PMSignalData *PMSignalState;
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extern int pgStatSock;
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#ifndef WIN32
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@ -4395,6 +4434,7 @@ save_backend_variables(BackendParameters * param, Port *port,
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memcpy(¶m->ListenSocket, &ListenSocket, sizeof(ListenSocket));
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param->MyCancelKey = MyCancelKey;
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param->MyPMChildSlot = MyPMChildSlot;
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param->UsedShmemSegID = UsedShmemSegID;
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param->UsedShmemSegAddr = UsedShmemSegAddr;
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@ -4407,6 +4447,7 @@ save_backend_variables(BackendParameters * param, Port *port,
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param->ProcStructLock = ProcStructLock;
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param->ProcGlobal = ProcGlobal;
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param->AuxiliaryProcs = AuxiliaryProcs;
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param->PMSignalState = PMSignalState;
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write_inheritable_socket(¶m->pgStatSock, pgStatSock, childPid);
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param->PostmasterPid = PostmasterPid;
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@ -4601,6 +4642,7 @@ restore_backend_variables(BackendParameters * param, Port *port)
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memcpy(&ListenSocket, ¶m->ListenSocket, sizeof(ListenSocket));
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MyCancelKey = param->MyCancelKey;
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MyPMChildSlot = param->MyPMChildSlot;
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UsedShmemSegID = param->UsedShmemSegID;
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UsedShmemSegAddr = param->UsedShmemSegAddr;
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@ -4613,6 +4655,7 @@ restore_backend_variables(BackendParameters * param, Port *port)
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ProcStructLock = param->ProcStructLock;
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ProcGlobal = param->ProcGlobal;
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AuxiliaryProcs = param->AuxiliaryProcs;
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PMSignalState = param->PMSignalState;
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read_inheritable_socket(&pgStatSock, ¶m->pgStatSock);
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PostmasterPid = param->PostmasterPid;
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@ -4642,7 +4685,7 @@ restore_backend_variables(BackendParameters * param, Port *port)
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Size
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ShmemBackendArraySize(void)
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{
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return mul_size(NUM_BACKENDARRAY_ELEMS, sizeof(Backend));
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return mul_size(MaxLivePostmasterChildren(), sizeof(Backend));
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}
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void
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@ -4658,41 +4701,23 @@ ShmemBackendArrayAllocation(void)
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static void
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ShmemBackendArrayAdd(Backend *bn)
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{
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int i;
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/* The array slot corresponding to my PMChildSlot should be free */
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int i = bn->child_slot - 1;
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/* Find an empty slot */
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for (i = 0; i < NUM_BACKENDARRAY_ELEMS; i++)
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{
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if (ShmemBackendArray[i].pid == 0)
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{
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ShmemBackendArray[i] = *bn;
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return;
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}
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}
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ereport(FATAL,
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(errmsg_internal("no free slots in shmem backend array")));
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Assert(ShmemBackendArray[i].pid == 0);
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ShmemBackendArray[i] = *bn;
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}
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static void
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ShmemBackendArrayRemove(pid_t pid)
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ShmemBackendArrayRemove(Backend *bn)
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{
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int i;
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int i = bn->child_slot - 1;
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for (i = 0; i < NUM_BACKENDARRAY_ELEMS; i++)
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{
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if (ShmemBackendArray[i].pid == pid)
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{
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/* Mark the slot as empty */
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ShmemBackendArray[i].pid = 0;
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return;
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}
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}
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ereport(WARNING,
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(errmsg_internal("could not find backend entry with pid %d",
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(int) pid)));
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Assert(ShmemBackendArray[i].pid == bn->pid);
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/* Mark the slot as empty */
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ShmemBackendArray[i].pid = 0;
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}
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#endif /* EXEC_BACKEND */
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.99 2009/01/03 17:08:39 tgl Exp $
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* $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.100 2009/05/05 19:59:00 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -111,6 +111,7 @@ CreateSharedMemoryAndSemaphores(bool makePrivate, int port)
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size = add_size(size, ProcArrayShmemSize());
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size = add_size(size, BackendStatusShmemSize());
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size = add_size(size, SInvalShmemSize());
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size = add_size(size, PMSignalShmemSize());
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size = add_size(size, BgWriterShmemSize());
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size = add_size(size, AutoVacuumShmemSize());
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size = add_size(size, BTreeShmemSize());
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@ -206,7 +207,7 @@ CreateSharedMemoryAndSemaphores(bool makePrivate, int port)
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/*
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* Set up interprocess signaling mechanisms
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*/
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PMSignalInit();
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PMSignalShmemInit();
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BgWriterShmemInit();
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AutoVacuumShmemInit();
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/storage/ipc/pmsignal.c,v 1.26 2009/01/01 17:23:47 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/storage/ipc/pmsignal.c,v 1.27 2009/05/05 19:59:00 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -34,26 +34,69 @@
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* The flags are actually declared as "volatile sig_atomic_t" for maximum
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* portability. This should ensure that loads and stores of the flag
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* values are atomic, allowing us to dispense with any explicit locking.
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*
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* In addition to the per-reason flags, we store a set of per-child-process
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* flags that are currently used only for detecting whether a backend has
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* exited without performing proper shutdown. The per-child-process flags
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* have three possible states: UNUSED, ASSIGNED, ACTIVE. An UNUSED slot is
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* available for assignment. An ASSIGNED slot is associated with a postmaster
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* child process, but either the process has not touched shared memory yet,
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* or it has successfully cleaned up after itself. A ACTIVE slot means the
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* process is actively using shared memory. The slots are assigned to
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* child processes at random, and postmaster.c is responsible for tracking
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* which one goes with which PID.
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*/
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static volatile sig_atomic_t *PMSignalFlags;
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#define PM_CHILD_UNUSED 0 /* these values must fit in sig_atomic_t */
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#define PM_CHILD_ASSIGNED 1
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#define PM_CHILD_ACTIVE 2
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/* "typedef struct PMSignalData PMSignalData" appears in pmsignal.h */
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struct PMSignalData
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{
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/* per-reason flags */
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sig_atomic_t PMSignalFlags[NUM_PMSIGNALS];
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/* per-child-process flags */
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int num_child_flags; /* # of entries in PMChildFlags[] */
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int next_child_flag; /* next slot to try to assign */
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sig_atomic_t PMChildFlags[1]; /* VARIABLE LENGTH ARRAY */
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};
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NON_EXEC_STATIC volatile PMSignalData *PMSignalState = NULL;
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/*
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* PMSignalInit - initialize during shared-memory creation
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* PMSignalShmemSize
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||||
* Compute space needed for pmsignal.c's shared memory
|
||||
*/
|
||||
Size
|
||||
PMSignalShmemSize(void)
|
||||
{
|
||||
Size size;
|
||||
|
||||
size = offsetof(PMSignalData, PMChildFlags);
|
||||
size = add_size(size, mul_size(MaxLivePostmasterChildren(),
|
||||
sizeof(sig_atomic_t)));
|
||||
|
||||
return size;
|
||||
}
|
||||
|
||||
/*
|
||||
* PMSignalShmemInit - initialize during shared-memory creation
|
||||
*/
|
||||
void
|
||||
PMSignalInit(void)
|
||||
PMSignalShmemInit(void)
|
||||
{
|
||||
bool found;
|
||||
|
||||
PMSignalFlags = (sig_atomic_t *)
|
||||
ShmemInitStruct("PMSignalFlags",
|
||||
NUM_PMSIGNALS * sizeof(sig_atomic_t),
|
||||
&found);
|
||||
PMSignalState = (PMSignalData *)
|
||||
ShmemInitStruct("PMSignalState", PMSignalShmemSize(), &found);
|
||||
|
||||
if (!found)
|
||||
MemSet(PMSignalFlags, 0, NUM_PMSIGNALS * sizeof(sig_atomic_t));
|
||||
{
|
||||
MemSet(PMSignalState, 0, PMSignalShmemSize());
|
||||
PMSignalState->num_child_flags = MaxLivePostmasterChildren();
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
@ -66,7 +109,7 @@ SendPostmasterSignal(PMSignalReason reason)
|
||||
if (!IsUnderPostmaster)
|
||||
return;
|
||||
/* Atomically set the proper flag */
|
||||
PMSignalFlags[reason] = true;
|
||||
PMSignalState->PMSignalFlags[reason] = true;
|
||||
/* Send signal to postmaster */
|
||||
kill(PostmasterPid, SIGUSR1);
|
||||
}
|
||||
@ -80,14 +123,105 @@ bool
|
||||
CheckPostmasterSignal(PMSignalReason reason)
|
||||
{
|
||||
/* Careful here --- don't clear flag if we haven't seen it set */
|
||||
if (PMSignalFlags[reason])
|
||||
if (PMSignalState->PMSignalFlags[reason])
|
||||
{
|
||||
PMSignalFlags[reason] = false;
|
||||
PMSignalState->PMSignalFlags[reason] = false;
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* AssignPostmasterChildSlot - select an unused slot for a new postmaster
|
||||
* child process, and set its state to ASSIGNED. Returns a slot number
|
||||
* (one to N).
|
||||
*
|
||||
* Only the postmaster is allowed to execute this routine, so we need no
|
||||
* special locking.
|
||||
*/
|
||||
int
|
||||
AssignPostmasterChildSlot(void)
|
||||
{
|
||||
int slot = PMSignalState->next_child_flag;
|
||||
int n;
|
||||
|
||||
/*
|
||||
* Scan for a free slot. We track the last slot assigned so as not to
|
||||
* waste time repeatedly rescanning low-numbered slots.
|
||||
*/
|
||||
for (n = PMSignalState->num_child_flags; n > 0; n--)
|
||||
{
|
||||
if (--slot < 0)
|
||||
slot = PMSignalState->num_child_flags - 1;
|
||||
if (PMSignalState->PMChildFlags[slot] == PM_CHILD_UNUSED)
|
||||
{
|
||||
PMSignalState->PMChildFlags[slot] = PM_CHILD_ASSIGNED;
|
||||
PMSignalState->next_child_flag = slot;
|
||||
return slot + 1;
|
||||
}
|
||||
}
|
||||
|
||||
/* Out of slots ... should never happen, else postmaster.c messed up */
|
||||
elog(FATAL, "no free slots in PMChildFlags array");
|
||||
return 0; /* keep compiler quiet */
|
||||
}
|
||||
|
||||
/*
|
||||
* ReleasePostmasterChildSlot - release a slot after death of a postmaster
|
||||
* child process. This must be called in the postmaster process.
|
||||
*
|
||||
* Returns true if the slot had been in ASSIGNED state (the expected case),
|
||||
* false otherwise (implying that the child failed to clean itself up).
|
||||
*/
|
||||
bool
|
||||
ReleasePostmasterChildSlot(int slot)
|
||||
{
|
||||
bool result;
|
||||
|
||||
Assert(slot > 0 && slot <= PMSignalState->num_child_flags);
|
||||
slot--;
|
||||
/*
|
||||
* Note: the slot state might already be unused, because the logic in
|
||||
* postmaster.c is such that this might get called twice when a child
|
||||
* crashes. So we don't try to Assert anything about the state.
|
||||
*/
|
||||
result = (PMSignalState->PMChildFlags[slot] == PM_CHILD_ASSIGNED);
|
||||
PMSignalState->PMChildFlags[slot] = PM_CHILD_UNUSED;
|
||||
return result;
|
||||
}
|
||||
|
||||
/*
|
||||
* MarkPostmasterChildActive - mark a postmaster child as about to begin
|
||||
* actively using shared memory. This is called in the child process.
|
||||
*/
|
||||
void
|
||||
MarkPostmasterChildActive(void)
|
||||
{
|
||||
int slot = MyPMChildSlot;
|
||||
|
||||
Assert(slot > 0 && slot <= PMSignalState->num_child_flags);
|
||||
slot--;
|
||||
Assert(PMSignalState->PMChildFlags[slot] == PM_CHILD_ASSIGNED);
|
||||
PMSignalState->PMChildFlags[slot] = PM_CHILD_ACTIVE;
|
||||
}
|
||||
|
||||
/*
|
||||
* MarkPostmasterChildInactive - mark a postmaster child as done using
|
||||
* shared memory. This is called in the child process.
|
||||
*/
|
||||
void
|
||||
MarkPostmasterChildInactive(void)
|
||||
{
|
||||
int slot = MyPMChildSlot;
|
||||
|
||||
Assert(slot > 0 && slot <= PMSignalState->num_child_flags);
|
||||
slot--;
|
||||
Assert(PMSignalState->PMChildFlags[slot] == PM_CHILD_ACTIVE);
|
||||
PMSignalState->PMChildFlags[slot] = PM_CHILD_ASSIGNED;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* PostmasterIsAlive - check whether postmaster process is still alive
|
||||
*
|
||||
|
@ -8,7 +8,7 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/storage/lmgr/proc.c,v 1.205 2009/01/01 17:23:48 momjian Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/storage/lmgr/proc.c,v 1.206 2009/05/05 19:59:00 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -41,6 +41,7 @@
|
||||
#include "postmaster/autovacuum.h"
|
||||
#include "storage/ipc.h"
|
||||
#include "storage/lmgr.h"
|
||||
#include "storage/pmsignal.h"
|
||||
#include "storage/proc.h"
|
||||
#include "storage/procarray.h"
|
||||
#include "storage/spin.h"
|
||||
@ -274,6 +275,14 @@ InitProcess(void)
|
||||
errmsg("sorry, too many clients already")));
|
||||
}
|
||||
|
||||
/*
|
||||
* Now that we have a PGPROC, mark ourselves as an active postmaster
|
||||
* child; this is so that the postmaster can detect it if we exit
|
||||
* without cleaning up.
|
||||
*/
|
||||
if (IsUnderPostmaster)
|
||||
MarkPostmasterChildActive();
|
||||
|
||||
/*
|
||||
* Initialize all fields of MyProc, except for the semaphore which was
|
||||
* prepared for us by InitProcGlobal.
|
||||
@ -614,6 +623,13 @@ ProcKill(int code, Datum arg)
|
||||
|
||||
SpinLockRelease(ProcStructLock);
|
||||
|
||||
/*
|
||||
* This process is no longer present in shared memory in any meaningful
|
||||
* way, so tell the postmaster we've cleaned up acceptably well.
|
||||
*/
|
||||
if (IsUnderPostmaster)
|
||||
MarkPostmasterChildInactive();
|
||||
|
||||
/* wake autovac launcher if needed -- see comments in FreeWorkerInfo */
|
||||
if (AutovacuumLauncherPid != 0)
|
||||
kill(AutovacuumLauncherPid, SIGUSR1);
|
||||
|
@ -8,7 +8,7 @@
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/utils/init/globals.c,v 1.107 2009/01/01 17:23:51 momjian Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/utils/init/globals.c,v 1.108 2009/05/05 19:59:00 tgl Exp $
|
||||
*
|
||||
* NOTES
|
||||
* Globals used all over the place should be declared here and not
|
||||
@ -36,6 +36,7 @@ int MyProcPid;
|
||||
pg_time_t MyStartTime;
|
||||
struct Port *MyProcPort;
|
||||
long MyCancelKey;
|
||||
int MyPMChildSlot;
|
||||
|
||||
/*
|
||||
* DataDir is the absolute path to the top level of the PGDATA directory tree.
|
||||
|
@ -13,7 +13,7 @@
|
||||
* Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/miscadmin.h,v 1.209 2009/01/05 02:27:45 alvherre Exp $
|
||||
* $PostgreSQL: pgsql/src/include/miscadmin.h,v 1.210 2009/05/05 19:59:00 tgl Exp $
|
||||
*
|
||||
* NOTES
|
||||
* some of the information in this file should be moved to other files.
|
||||
@ -137,6 +137,7 @@ extern PGDLLIMPORT int MyProcPid;
|
||||
extern PGDLLIMPORT pg_time_t MyStartTime;
|
||||
extern PGDLLIMPORT struct Port *MyProcPort;
|
||||
extern long MyCancelKey;
|
||||
extern int MyPMChildSlot;
|
||||
|
||||
extern char OutputFileName[];
|
||||
extern PGDLLIMPORT char my_exec_path[];
|
||||
|
@ -6,7 +6,7 @@
|
||||
* Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/postmaster/postmaster.h,v 1.19 2009/01/01 17:24:01 momjian Exp $
|
||||
* $PostgreSQL: pgsql/src/include/postmaster/postmaster.h,v 1.20 2009/05/05 19:59:00 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -38,6 +38,8 @@ extern const char *progname;
|
||||
extern int PostmasterMain(int argc, char *argv[]);
|
||||
extern void ClosePostmasterPorts(bool am_syslogger);
|
||||
|
||||
extern int MaxLivePostmasterChildren(void);
|
||||
|
||||
#ifdef EXEC_BACKEND
|
||||
extern pid_t postmaster_forkexec(int argc, char *argv[]);
|
||||
extern int SubPostmasterMain(int argc, char *argv[]);
|
||||
|
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/storage/pmsignal.h,v 1.23 2009/02/23 09:28:50 heikki Exp $
|
||||
* $PostgreSQL: pgsql/src/include/storage/pmsignal.h,v 1.24 2009/05/05 19:59:00 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -33,12 +33,20 @@ typedef enum
|
||||
NUM_PMSIGNALS /* Must be last value of enum! */
|
||||
} PMSignalReason;
|
||||
|
||||
/* PMSignalData is an opaque struct, details known only within pmsignal.c */
|
||||
typedef struct PMSignalData PMSignalData;
|
||||
|
||||
/*
|
||||
* prototypes for functions in pmsignal.c
|
||||
*/
|
||||
extern void PMSignalInit(void);
|
||||
extern Size PMSignalShmemSize(void);
|
||||
extern void PMSignalShmemInit(void);
|
||||
extern void SendPostmasterSignal(PMSignalReason reason);
|
||||
extern bool CheckPostmasterSignal(PMSignalReason reason);
|
||||
extern int AssignPostmasterChildSlot(void);
|
||||
extern bool ReleasePostmasterChildSlot(int slot);
|
||||
extern void MarkPostmasterChildActive(void);
|
||||
extern void MarkPostmasterChildInactive(void);
|
||||
extern bool PostmasterIsAlive(bool amDirectChild);
|
||||
|
||||
#endif /* PMSIGNAL_H */
|
||||
|
Loading…
Reference in New Issue
Block a user