Improve docs and error messages for parallel vacuum.

The error messages, docs, and one of the options were using
'parallel degree' to indicate parallelism used by vacuum command. We
normally use 'parallel workers' at other places so change it for parallel
vacuum accordingly.

Author: Bharath Rupireddy
Reviewed-by: Dilip Kumar, Amit Kapila
Backpatch-through: 13
Discussion: https://postgr.es/m/CALj2ACWz=PYrrFXVsEKb9J1aiX4raA+UBe02hdRp_zqDkrWUiw@mail.gmail.com

diff --git a/doc/src/sgml/ref/vacuumdb.sgml b/doc/src/sgml/ref/vacuumdb.sgml
index eeafed7fbe23aa22d165c487c5ce3cad2c90f088..61c2e7d237330fe3a340e3673b228d72ff9edda6 100644 (file)
--- a/doc/src/sgml/ref/vacuumdb.sgml
+++ b/doc/src/sgml/ref/vacuumdb.sgml
@@ -230,11 +230,11 @@ PostgreSQL documentation
      </varlistentry>
 
      <varlistentry>
-      <term><option>-P <replaceable class="parameter">parallel_degree</replaceable></option></term>
-      <term><option>--parallel=<replaceable class="parameter">parallel_degree</replaceable></option></term>
+      <term><option>-P <replaceable class="parameter">parallel_workers</replaceable></option></term>
+      <term><option>--parallel=<replaceable class="parameter">parallel_workers</replaceable></option></term>
       <listitem>
        <para>
-        Specify the parallel degree of <firstterm>parallel vacuum</firstterm>.
+        Specify the number of parallel workers for <firstterm>parallel vacuum</firstterm>.
         This allows the vacuum to leverage multiple CPUs to process indexes.
         See <xref linkend="sql-vacuum"/>.
        </para>

diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 92c4eb6a876ffabf3f74ed4345c1a8c6281dbf4e..5ef6698790c49390ff9b43e2aff4a18a3f4f6f42 100644 (file)
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -160,7 +160,7 @@ ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel)
                                if (nworkers < 0 || nworkers > MAX_PARALLEL_WORKER_LIMIT)
                                        ereport(ERROR,
                                                        (errcode(ERRCODE_SYNTAX_ERROR),
-                                                        errmsg("parallel vacuum degree must be between 0 and %d",
+                                                        errmsg("parallel workers for vacuum must be between 0 and %d",
                                                                        MAX_PARALLEL_WORKER_LIMIT),
                                                         parser_errposition(pstate, opt->location)));
 

diff --git a/src/bin/scripts/vacuumdb.c b/src/bin/scripts/vacuumdb.c
index 3e57fa9a8614f50ed63a35ff0fa57412b497e1f0..1cf689cd053babfc4940b982fe770f1268706c53 100644 (file)
--- a/src/bin/scripts/vacuumdb.c
+++ b/src/bin/scripts/vacuumdb.c
@@ -189,7 +189,7 @@ main(int argc, char *argv[])
                                vacopts.parallel_workers = atoi(optarg);
                                if (vacopts.parallel_workers < 0)
                                {
-                                       pg_log_error("parallel vacuum degree must be a non-negative integer");
+                                       pg_log_error("parallel workers for vacuum must be greater than or equal to zero");
                                        exit(1);
                                }
                                break;
@@ -920,7 +920,7 @@ help(const char *progname)
        printf(_("  -j, --jobs=NUM                  use this many concurrent connections to vacuum\n"));
        printf(_("      --min-mxid-age=MXID_AGE     minimum multixact ID age of tables to vacuum\n"));
        printf(_("      --min-xid-age=XID_AGE       minimum transaction ID age of tables to vacuum\n"));
-       printf(_("  -P, --parallel=PARALLEL_DEGREE  use this many background workers for vacuum, if available\n"));
+       printf(_("  -P, --parallel=PARALLEL_WORKERS use this many background workers for vacuum, if available\n"));
        printf(_("  -q, --quiet                     don't write any messages\n"));
        printf(_("      --skip-locked               skip relations that cannot be immediately locked\n"));
        printf(_("  -t, --table='TABLE[(COLUMNS)]'  vacuum specific table(s) only\n"));

diff --git a/src/test/regress/expected/vacuum.out b/src/test/regress/expected/vacuum.out
index 3fccb183c0fd4789a2eb616053b1b18b4146ae77..d026847c155b082a35f14bcb1f532fc3259a859c 100644 (file)
--- a/src/test/regress/expected/vacuum.out
+++ b/src/test/regress/expected/vacuum.out
@@ -110,7 +110,7 @@ VACUUM (PARALLEL 2) pvactst;
 UPDATE pvactst SET i = i WHERE i < 1000;
 VACUUM (PARALLEL 0) pvactst; -- disable parallel vacuum
 VACUUM (PARALLEL -1) pvactst; -- error
-ERROR:  parallel vacuum degree must be between 0 and 1024
+ERROR:  parallel workers for vacuum must be between 0 and 1024
 LINE 1: VACUUM (PARALLEL -1) pvactst;
                 ^
 VACUUM (PARALLEL 2, INDEX_CLEANUP FALSE) pvactst;