From e6cabe717637cf4095cfae85806e199a122935d3 Mon Sep 17 00:00:00 2001 From: Peter Smith Date: Fri, 11 Aug 2023 19:41:39 +1000 Subject: [PATCH v7] Simplify determining logical replication worker types. We deduce a LogicalRepWorker's type from the values of several different fields ('relid' and 'leader_pid') whenever logic needs to know it. In fact, the logical replication worker type is already known at the time of launching the LogicalRepWorker and it never changes for the lifetime of that process. Instead of deducing the type, it is simpler to just store it one time, and access it directly thereafter. Author: Peter Smith Reviewed-by: Amit Kapila, Bharath Rupireddy Discussion: http://postgr.es/m/CAHut+PttPSuP0yoZ=9zLDXKqTJ=d0bhxwKaEaNcaym1XqcvDEg@mail.gmail.com --- .../replication/logical/applyparallelworker.c | 3 ++- src/backend/replication/logical/launcher.c | 27 +++++++++++++++------- src/backend/replication/logical/tablesync.c | 3 ++- src/include/replication/worker_internal.h | 21 +++++++++++++---- src/tools/pgindent/typedefs.list | 1 + 5 files changed, 40 insertions(+), 15 deletions(-) diff --git a/src/backend/replication/logical/applyparallelworker.c b/src/backend/replication/logical/applyparallelworker.c index 1d4e83c..4e8ee29 100644 --- a/src/backend/replication/logical/applyparallelworker.c +++ b/src/backend/replication/logical/applyparallelworker.c @@ -435,7 +435,8 @@ pa_launch_parallel_worker(void) return NULL; } - launched = logicalrep_worker_launch(MyLogicalRepWorker->dbid, + launched = logicalrep_worker_launch(WORKERTYPE_PARALLEL_APPLY, + MyLogicalRepWorker->dbid, MySubscription->oid, MySubscription->name, MyLogicalRepWorker->userid, diff --git a/src/backend/replication/logical/launcher.c b/src/backend/replication/logical/launcher.c index e231fa7..7454c8c 100644 --- a/src/backend/replication/logical/launcher.c +++ b/src/backend/replication/logical/launcher.c @@ -303,7 +303,8 @@ logicalrep_workers_find(Oid subid, bool only_running) * Returns true on success, false on failure. */ bool -logicalrep_worker_launch(Oid dbid, Oid subid, const char *subname, Oid userid, +logicalrep_worker_launch(LogicalRepWorkerType wtype, + Oid dbid, Oid subid, const char *subname, Oid userid, Oid relid, dsm_handle subworker_dsm) { BackgroundWorker bgw; @@ -315,10 +316,18 @@ logicalrep_worker_launch(Oid dbid, Oid subid, const char *subname, Oid userid, int nsyncworkers; int nparallelapplyworkers; TimestampTz now; - bool is_parallel_apply_worker = (subworker_dsm != DSM_HANDLE_INVALID); - - /* Sanity check - tablesync worker cannot be a subworker */ - Assert(!(is_parallel_apply_worker && OidIsValid(relid))); + bool is_tablesync_worker = (wtype == WORKERTYPE_TABLESYNC); + bool is_parallel_apply_worker = (wtype == WORKERTYPE_PARALLEL_APPLY); + + /*---------- + * Sanity checks: + * - must be valid worker type + * - tablesync workers are only ones to have relid + * - parallel apply worker is the only kind of subworker + */ + Assert(wtype != WORKERTYPE_UNKNOWN); + Assert(is_tablesync_worker == OidIsValid(relid)); + Assert(is_parallel_apply_worker == (subworker_dsm != DSM_HANDLE_INVALID)); ereport(DEBUG1, (errmsg_internal("starting logical replication worker for subscription \"%s\"", @@ -393,7 +402,7 @@ retry: * sync worker limit per subscription. So, just return silently as we * might get here because of an otherwise harmless race condition. */ - if (OidIsValid(relid) && nsyncworkers >= max_sync_workers_per_subscription) + if (is_tablesync_worker && nsyncworkers >= max_sync_workers_per_subscription) { LWLockRelease(LogicalRepWorkerLock); return false; @@ -427,6 +436,7 @@ retry: } /* Prepare the worker slot. */ + worker->type = wtype; worker->launch_time = now; worker->in_use = true; worker->generation++; @@ -466,7 +476,7 @@ retry: subid); snprintf(bgw.bgw_type, BGW_MAXLEN, "logical replication parallel worker"); } - else if (OidIsValid(relid)) + else if (is_tablesync_worker) { snprintf(bgw.bgw_function_name, BGW_MAXLEN, "TablesyncWorkerMain"); snprintf(bgw.bgw_name, BGW_MAXLEN, @@ -1180,7 +1190,8 @@ ApplyLauncherMain(Datum main_arg) (elapsed = TimestampDifferenceMilliseconds(last_start, now)) >= wal_retrieve_retry_interval) { ApplyLauncherSetWorkerStartTime(sub->oid, now); - logicalrep_worker_launch(sub->dbid, sub->oid, sub->name, + logicalrep_worker_launch(WORKERTYPE_APPLY, + sub->dbid, sub->oid, sub->name, sub->owner, InvalidOid, DSM_HANDLE_INVALID); } diff --git a/src/backend/replication/logical/tablesync.c b/src/backend/replication/logical/tablesync.c index 651a775..67bdd14 100644 --- a/src/backend/replication/logical/tablesync.c +++ b/src/backend/replication/logical/tablesync.c @@ -587,7 +587,8 @@ process_syncing_tables_for_apply(XLogRecPtr current_lsn) TimestampDifferenceExceeds(hentry->last_start_time, now, wal_retrieve_retry_interval)) { - logicalrep_worker_launch(MyLogicalRepWorker->dbid, + logicalrep_worker_launch(WORKERTYPE_TABLESYNC, + MyLogicalRepWorker->dbid, MySubscription->oid, MySubscription->name, MyLogicalRepWorker->userid, diff --git a/src/include/replication/worker_internal.h b/src/include/replication/worker_internal.h index 672a711..d5c9de4 100644 --- a/src/include/replication/worker_internal.h +++ b/src/include/replication/worker_internal.h @@ -27,9 +27,20 @@ #include "storage/shm_toc.h" #include "storage/spin.h" +/* Different types of worker */ +typedef enum LogicalRepWorkerType +{ + WORKERTYPE_UNKNOWN = 0, + WORKERTYPE_TABLESYNC, + WORKERTYPE_APPLY, + WORKERTYPE_PARALLEL_APPLY +} LogicalRepWorkerType; typedef struct LogicalRepWorker { + /* What type of worker is this? */ + LogicalRepWorkerType type; + /* Time at which this worker was launched. */ TimestampTz launch_time; @@ -232,7 +243,8 @@ extern void logicalrep_worker_attach(int slot); extern LogicalRepWorker *logicalrep_worker_find(Oid subid, Oid relid, bool only_running); extern List *logicalrep_workers_find(Oid subid, bool only_running); -extern bool logicalrep_worker_launch(Oid dbid, Oid subid, const char *subname, +extern bool logicalrep_worker_launch(LogicalRepWorkerType wtype, + Oid dbid, Oid subid, const char *subname, Oid userid, Oid relid, dsm_handle subworker_dsm); extern void logicalrep_worker_stop(Oid subid, Oid relid); @@ -315,19 +327,18 @@ extern void pa_decr_and_wait_stream_block(void); extern void pa_xact_finish(ParallelApplyWorkerInfo *winfo, XLogRecPtr remote_lsn); -#define isParallelApplyWorker(worker) ((worker)->leader_pid != InvalidPid) +#define isParallelApplyWorker(worker) ((worker)->type == WORKERTYPE_PARALLEL_APPLY) static inline bool am_tablesync_worker(void) { - return OidIsValid(MyLogicalRepWorker->relid); + return (MyLogicalRepWorker->type == WORKERTYPE_TABLESYNC); } static inline bool am_leader_apply_worker(void) { - return (!am_tablesync_worker() && - !isParallelApplyWorker(MyLogicalRepWorker)); + return (MyLogicalRepWorker->type == WORKERTYPE_APPLY); } static inline bool diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list index 66823bc..52a8789 100644 --- a/src/tools/pgindent/typedefs.list +++ b/src/tools/pgindent/typedefs.list @@ -1500,6 +1500,7 @@ LogicalRepStreamAbortData LogicalRepTupleData LogicalRepTyp LogicalRepWorker +LogicalRepWorkerType LogicalRewriteMappingData LogicalTape LogicalTapeSet -- 1.8.3.1