On Fri, Apr 15, 2016 at 6:56 PM, Magnus Hagander <mag...@hagander.net> wrote: > The documentation says that the default value is 128Kb on Linux, but the > code says it's 256Kb. > > Not sure which one is correct, but the other one should be updated :) I'm > guessing it's a copy/paste mistake in the docs, but since I'm not sure I'm > not just pushing a fix.
I think you're right. I also found another several small problems regarding XXX_flush_after parameters. (1) checkpoint_flush_after, backend_flush_after and bgwriter_flush_after don't exist in postgresql.conf.sample. If there is no special reason for that, it's better to add them to postgresql.conf.sample. (2) > /* see bufmgr.h: 16 on Linux, 0 otherwise */ The source code comment says that the default value of bgwriter_flush_after is 16 on Linux, but it's actually 64. The parameter which its default is 16 is backend_flush_after. This souce comment needs to be updated. (3) The config groups assigned to them look strange. The group of checkpoint_flush_after is RESOURCES_ASYNCHRONOUS, but it's documented under the section "Checkpoints". IMO, it's better to change the group to WAL_CHECKPOINTS. The group of bgwriter_flush_after is WAL_CHECKPOINTS, but it's documented under the section Background Writer. IMO, it's better to change the group to RESOURCES_BGWRITER. (4) > This parameter can only be set in the postgresql.conf file or on > the server command line. The above description should be used for a PGC_SIGHUP parameter. But it's used for backend_flush_after which is PGC_USERSET parameter. (5) <term><varname>bgwriter_flush_after</varname> (<type>int</type>) <term><varname>backend_flush_after</varname> (<type>int</type>) <term><varname>checkpoint_flush_after</varname> (<type>int</type>) In the doc, "int" should be "integer" for the sake of consistency. Regards, -- Fujii Masao -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers