-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 02/09/2015 15:53, Andres Freund wrote: > On 2015-07-18 12:17:39 +0200, Julien Rouhaud wrote: > > You also didn't touch /* * How many buffers PrefetchBuffer callers > should try to stay ahead of their * ReadBuffer calls by. This is > maintained by the assign hook for * effective_io_concurrency. Zero > means "never prefetch". */ int target_prefetch_pages = > 0; which > surely doesn't make sense anymore after these changes. > > But do we even need that variable now? >
I thought this was related to the effective_io_concurrency GUC (possibly overloaded by the per-tablespace setting), so I didn't make any change on that. I also just found an issue with my previous patch, the global effective_io_concurrency GUC was ignored if the tablespace had a specific seq_page_cost or random_page_cost setting, I just fixed that in my local branch. >> diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h >> index dc167f9..57008fc 100644 --- a/src/include/utils/guc.h +++ >> b/src/include/utils/guc.h @@ -26,6 +26,9 @@ #define MAX_KILOBYTES >> (INT_MAX / 1024) #endif >> >> +/* upper limit for effective_io_concurrency */ +#define >> MAX_IO_CONCURRENCY 1000 + /* * Automatic configuration file name >> for ALTER SYSTEM. * This file will be used to store values of >> configuration parameters @@ -256,6 +259,8 @@ extern int >> temp_file_limit; >> >> extern int num_temp_buffers; >> >> +extern int effective_io_concurrency; + > > target_prefetch_pages is declared in bufmgr.h - that seems like a > better place for these. > I was rather sceptical about that too. I'll move these in bufmgr.h. Regards. - -- Julien Rouhaud http://dalibo.com - http://dalibo.org -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (GNU/Linux) iQEcBAEBAgAGBQJV51pcAAoJELGaJ8vfEpOqIV0H/Rj1e/DtJS60X2mReWDyfooD G3j0Ptblhy+brYIIxo9Bdp9hVeYFmEqlOJIht9T/3gjfkg5IMz+5bV2waEbAan/m 9uedR/RmS9sz2YpwGgpd21bfSt2LwB+UC448t3rq8KtuzwmXgSVVEflmDmN1qV3z PseUFzS74HeIJWfxLRLGsJ5amN0hJ8bdolIfxdFR0FyFDv0tRv1DzppdMebVJmHs uIdJOU49sIDHjcnsUcq67jkP+IfTUon+nnwvk5FYVVKdBX2ka1Q/1VAvTfmWo0oV WZSlIjQdMUnlTX91zke0NdmsTnagIeRy1oISn/K1v+YmSqnsPqPAcZ6FFQhUMqI= =4ofZ -----END PGP SIGNATURE----- -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
