From dbdfd114f34443f1e4ad16ce2721f9817d3b3d80 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 25 Nov 2016 18:36:10 -0500 Subject: Bring some clarity to the defaults for the xxx_flush_after parameters. Instead of confusingly stating platform-dependent defaults for these parameters in the comments in postgresql.conf.sample (with the main entry being a lie on Linux), teach initdb to install the correct platform-dependent value in postgresql.conf, similarly to the way we handle other platform-dependent defaults. This won't do anything for existing 9.6 installations, but since it's effectively only a documentation improvement, that seems OK. Since this requires initdb to have access to the default values, move the #define's for those to pg_config_manual.h; the original placement in bufmgr.h is unworkable because that file can't be included by frontend programs. Adjust the default value for wal_writer_flush_after so that it is 1MB regardless of XLOG_BLCKSZ, conforming to what is stated in both the SGML docs and postgresql.conf. (We could alternatively make it scale with XLOG_BLCKSZ, but I'm not sure I see the point.) Copy-edit related SGML documentation. Fabien Coelho and Tom Lane, per a gripe from Tomas Vondra. Discussion: <30ebc6e3-8358-09cf-44a8-578252938424@2ndquadrant.com> --- src/backend/utils/misc/postgresql.conf.sample | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'src/backend/utils/misc/postgresql.conf.sample') diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index 7c2daa54bc8..0df15380a9a 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -156,8 +156,7 @@ #bgwriter_delay = 200ms # 10-10000ms between rounds #bgwriter_lru_maxpages = 100 # 0-1000 max buffers written/round #bgwriter_lru_multiplier = 2.0 # 0-10.0 multiplier on buffers scanned/round -#bgwriter_flush_after = 0 # 0 disables, - # default is 512kB on linux, 0 otherwise +#bgwriter_flush_after = 0 # measured in pages, 0 disables # - Asynchronous Behavior - @@ -166,7 +165,7 @@ #max_parallel_workers_per_gather = 2 # taken from max_worker_processes #old_snapshot_threshold = -1 # 1min-60d; -1 disables; 0 is immediate # (change requires restart) -#backend_flush_after = 0 # 0 disables, default is 0 +#backend_flush_after = 0 # measured in pages, 0 disables #------------------------------------------------------------------------------ @@ -196,7 +195,7 @@ #wal_buffers = -1 # min 32kB, -1 sets based on shared_buffers # (change requires restart) #wal_writer_delay = 200ms # 1-10000 milliseconds -#wal_writer_flush_after = 1MB # 0 disables +#wal_writer_flush_after = 1MB # measured in pages, 0 disables #commit_delay = 0 # range 0-100000, in microseconds #commit_siblings = 5 # range 1-1000 @@ -207,8 +206,7 @@ #max_wal_size = 1GB #min_wal_size = 80MB #checkpoint_completion_target = 0.5 # checkpoint target duration, 0.0 - 1.0 -#checkpoint_flush_after = 0 # 0 disables, - # default is 256kB on linux, 0 otherwise +#checkpoint_flush_after = 0 # measured in pages, 0 disables #checkpoint_warning = 30s # 0 disables # - Archiving - -- cgit v1.2.3