pgsql: Add a multi-worker capability to autovacuum. - Mailing list pgsql-committers

Log Message:
-----------
Add a multi-worker capability to autovacuum.  This allows multiple worker
processes to be running simultaneously.  Also, now autovacuum processes do not
count towards the max_connections limit; they are counted separately from
regular processes, and are limited by the new GUC variable
autovacuum_max_workers.

The launcher now has intelligence to launch workers on each database every
autovacuum_naptime seconds, limited only on the max amount of worker slots
available.

Also, the global worker I/O utilization is limited by the vacuum cost-based
delay feature.  Workers are "balanced" so that the total I/O consumption does
not exceed the established limit.  This part of the patch was contributed by
ITAGAKI Takahiro.

Per discussion.

Modified Files:
--------------
    pgsql/doc/src/sgml:
        config.sgml (r1.119 -> r1.120)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/config.sgml.diff?r1=1.119&r2=1.120)
        maintenance.sgml (r1.70 -> r1.71)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/maintenance.sgml.diff?r1=1.70&r2=1.71)
    pgsql/src/backend/commands:
        vacuum.c (r1.349 -> r1.350)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/vacuum.c.diff?r1=1.349&r2=1.350)
    pgsql/src/backend/postmaster:
        autovacuum.c (r1.40 -> r1.41)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/postmaster/autovacuum.c.diff?r1=1.40&r2=1.41)
    pgsql/src/backend/storage/lmgr:
        proc.c (r1.187 -> r1.188)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/lmgr/proc.c.diff?r1=1.187&r2=1.188)
    pgsql/src/backend/utils/init:
        globals.c (r1.100 -> r1.101)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/init/globals.c.diff?r1=1.100&r2=1.101)
    pgsql/src/backend/utils/misc:
        guc.c (r1.384 -> r1.385)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/guc.c.diff?r1=1.384&r2=1.385)
        postgresql.conf.sample (r1.213 -> r1.214)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/postgresql.conf.sample.diff?r1=1.213&r2=1.214)
    pgsql/src/include:
        miscadmin.h (r1.193 -> r1.194)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/miscadmin.h.diff?r1=1.193&r2=1.194)
    pgsql/src/include/postmaster:
        autovacuum.h (r1.8 -> r1.9)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/postmaster/autovacuum.h.diff?r1=1.8&r2=1.9)
    pgsql/src/include/storage:
        lwlock.h (r1.35 -> r1.36)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/storage/lwlock.h.diff?r1=1.35&r2=1.36)
        proc.h (r1.97 -> r1.98)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/storage/proc.h.diff?r1=1.97&r2=1.98)