10000 Various fixes for compatibility with pg 15 by rjuju · Pull Request #49 · postgrespro/pg_wait_sampling · GitHub
[go: up one dir, main page]
Skip to content

Various fixes for compatibility with pg 15 #49

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 4 commits into from
May 20, 2022
Merged

Various fixes for compatibility with pg 15 #49

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
609975a
Remove _PG_fini().
rjuju May 14, 2022
4761667
Wait 1 second before restarting the bgworker.
rjuju May 14, 2022
1a8aa64
Setup SIGUSR1 procsignal_sigusr1_handler handler.
rjuju May 14, 2022
5b50e78
Fix compatibility with pg15 new shmem_request_hook.
rjuju May 14, 2022
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
13 changes: 12 additions & 1 deletion collector.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -44,7 +44,7 @@ register_wait_collector(void)
memset(&worker, 0, sizeof(worker));
worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
worker.bgw_start_time = BgWorkerStart_ConsistentState;
worker.bgw_restart_time = 0;
worker.bgw_restart_time = 1;
worker.bgw_notify_pid = 0;
snprintf(worker.bgw_library_name, BGW_MAXLEN, "pg_wait_sampling");
snprintf(worker.bgw_function_name, BGW_MAXLEN, CppAsString(collector_main));
Expand Down Expand Up @@ -339,8 +339,16 @@ collector_main(Datum main_arg)
* any equivalent of the backend's command-read loop, where interrupts can
* be processed immediately, so make sure ImmediateInterruptOK is turned
* off.
*
* We also want to respond to the ProcSignal notifications. This is done
* in the upstream provided procsignal_sigusr1_handler, which is
* automatically used if a bgworker connects to a database. But since our
* worker doesn't connect to any database even though it calls
* InitPostgres, which will still initializze a new backend and thus
* partitipate to the ProcSignal infrastructure.
*/
pqsignal(SIGTERM, handle_sigterm);
pqsignal(SIGUSR1, procsignal_sigusr1_handler);
BackgroundWorkerUnblockSignals();

#if PG_VERSION_NUM >= 110000
Expand Down Expand Up @@ -379,6 +387,9 @@ collector_main(Datum main_arg)
bool write_history,
write_profile;

/* We need an explicit call for at least ProcSignal notifications. */
CHECK_FOR_INTERRUPTS();

/* Wait calculate time to next sample for history or profile */
current_ts = GetCurrentTimestamp();

Expand Down
84 changes: 58 additions & 26 deletions pg_wait_sampling.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -39,7 +39,6 @@
PG_MODULE_MAGIC;

void _PG_init(void);
void _PG_fini(void);

/* Global variables */
bool shmem_initialized = false;
Expand All @@ -59,6 +58,9 @@ shm_mq *recv_mq = NULL;
shm_mq_handle *recv_mqh = NULL;
LOCKTAG queueTag;

#if PG_VERSION_NUM >= 150000
static shmem_request_hook_type prev_shmem_request_hook = NULL;
#endif
static shmem_startup_hook_type prev_shmem_startup_hook = NULL;
static PGPROC * search_proc(int backendPid);
static PlannedStmt *pgws_planner_hook(Query *parse,
Expand All @@ -74,28 +76,40 @@ static void pgws_ExecutorEnd(QueryDesc *queryDesc);
* The value has to be in sync with ProcGlobal->allProcCount, initialized in
* InitProcGlobal() (proc.c).
*
* We calculate the value here as it won't initialized when we need it during
* _PG_init().
*
* Note that the value returned during _PG_init() might be different from the
* value returned later if some third-party modules change one of the
* underlying GUC. This isn't ideal but can't lead to a crash, as the value
* returned during _PG_init() is only used to ask for additional shmem with
* RequestAddinShmemSpace(), and postgres has an extra 100kB of shmem to
* compensate some small unaccounted usage. So if the value later changes, we
* will allocate and initialize the new (and correct) memory size, which
* will either work thanks for the extra 100kB of shmem, of fail (and prevent
* postgres startup) due to an out of shared memory error.
*/
static int
get_max_procs_count(void)
{
int count = 0;

/* First, add the maximum number of backends (MaxBackends). */
#if PG_VERSION_NUM >= 150000
/*
* MaxBackends: bgworkers, autovacuum workers and launcher.
* On pg15+, we can directly access the MaxBackends variable, as it will
* have already been initialized in shmem_request_hook.
*/
Assert(MaxBackends > 0);
count += MaxBackends;
#else
/*
* On older versions, we need to compute MaxBackends: bgworkers, autovacuum
* workers and launcher.
* This has to be in sync with the value computed in
* InitializeMaxBackends() (postinit.c)
*
* Note that we need to calculate the value as it won't initialized when we
* need it during _PG_init().
*
* Note also that the value returned during _PG_init() might be different
* from the value returned later if some third-party modules change one of
* the underlying GUC. This isn't ideal but can't lead to a crash, as the
* value returned during _PG_init() is only used to ask for additional
* shmem with RequestAddinShmemSpace(), and postgres has an extra 100kB of
* shmem to compensate some small unaccounted usage. So if the value later
* changes, we will allocate and initialize the new (and correct) memory
* size, which will either work thanks for the extra 100kB of shmem, of
* fail (and prevent postgres startup) due to an out of shared memory
* error.
*/
count += MaxConnections + autovacuum_max_workers + 1
+ max_worker_processes;
Expand All @@ -106,9 +120,11 @@ get_max_procs_count(void)
*/
#if PG_VERSION_NUM >= 120000
count += max_wal_senders;
#endif
#endif /* pg 12+ */
#endif /* pg 15- */
/* End of MaxBackends calculation. */

/* AuxiliaryProcs */
/* Add AuxiliaryProcs */
count += NUM_AUXILIARY_PROCS;

return count;
Expand Down Expand Up @@ -266,6 +282,23 @@ setup_gucs()
}
}

#if PG_VERSION_NUM >= 150000
/*
* shmem_request hook: request additional shared memory resources.
*
* If you change code here, don't forget to also report the modifications in
* _PG_init() for pg14 and below.
*/
static void
pgws_shmem_request(void)
{
if (prev_shmem_request_hook)
prev_shmem_request_hook();

RequestAddinShmemSpace(pgws_shmem_size());
}
#endif

/*
* Distribute shared memory.
*/
Expand Down Expand Up @@ -345,18 +378,27 @@ _PG_init(void)
if (!process_shared_preload_libraries_in_progress)
return;

#if PG_VERSION_NUM < 150000
/*
* Request additional shared resources. (These are no-ops if we're not in
* the postmaster process.) We'll allocate or attach to the shared
* resources in pgws_shmem_startup().
*
* If you change code here, don't forget to also report the modifications
* in pgsp_shmem_request() for pg15 and later.
*/
RequestAddinShmemSpace(pgws_shmem_size());
#endif

register_wait_collector();

/*
* Install hooks.
*/
#if PG_VERSION_NUM >= 150000
prev_shmem_request_hook = shmem_request_hook;
shmem_request_hook = pgws_shmem_request;
#endif
prev_shmem_startup_hook = shmem_startup_hook;
shmem_startup_hook = pgws_shmem_startup;
planner_hook_next = planner_hook;
Expand All @@ -365,16 +407,6 @@ _PG_init(void)
ExecutorEnd_hook = pgws_ExecutorEnd;
}

/*
* Module unload callback
*/
void
_PG_fini(void)
{
/* Uninstall hooks. */
shmem_startup_hook = prev_shmem_startup_hook;
}

/*
* Find PGPROC entry responsible for given pid assuming ProcArrayLock was
* already taken.
Expand Down
0