Re: [WIP] cache estimates, cache access cost
Cédric Villemain <cedric.villemain.debian@gmail.com>
From: Cédric Villemain <cedric.villemain.debian@gmail.com>
To: Alvaro Herrera <alvherre@commandprompt.com>
Cc: Greg Smith <greg@2ndquadrant.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2011-06-14T21:10:20Z
Lists: pgsql-hackers
2011/6/14 Alvaro Herrera <alvherre@commandprompt.com>: > Excerpts from Cédric Villemain's message of mar jun 14 10:29:36 -0400 2011: > >> Attached are updated patches without the plugin itself. I've also >> added the cache_page_cost GUC, this one is not per tablespace, like >> others page_cost. >> >> There are 6 patches: >> >> 0001-Add-reloscache-column-to-pg_class.patch > > Hmm, do you really need this to be a new column? Would it work to have > it be a reloption? If we can have ALTER TABLE running on heavy workload, why not. I am bit scared by the effect of such reloption, it focus on HINT oriented strategy when I would like to allow a dynamic strategy from the server. This work is not done and may not work, so a reloption is good at least as a backup (and is more in the idea suggested by Tom and others) > > -- > Álvaro Herrera <alvherre@commandprompt.com> > The PostgreSQL Company - Command Prompt, Inc. > PostgreSQL Replication, Consulting, Custom Development, 24x7 support > -- Cédric Villemain 2ndQuadrant http://2ndQuadrant.fr/ PostgreSQL : Expertise, Formation et Support