[PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: 回复： [PERFORM] PG as in-memory db? How to warm up and re-populate buffers? How to read in all tuples into memory?

On 2.3.2012 03:05, Claudio Freire wrote: > On Thu, Mar 1, 2012 at 10:13 PM, Tomas Vondra wrote: >> >> Maybe. I still am not sure how fsync=off affects the eviction in your >> opinion. I think it does not (or just very remotely) and you were saying >> the opposite. IMHO the eviction of (dirty) buff

Re: [PERFORM] Inefficient min/max against partition (ver 9.1.1)

"McGehee, Robert" writes: > On PostgreSQL 9.1.1, I'm experiencing extremely slow/inefficient > min/max queries against a partitioned table, despite the recent > improvements made in version 9.1. Thanks for the report. I believe this will fix it: http://git.postgresql.org/gitweb/?p=postgresql.git

Re: [PERFORM] Large insert and delete batches

On 03/01/2012 10:51 PM, Marti Raudsepp wrote: The problem with IN() and ARRAY[] is that the whole list of numbers has to be parsed by the SQL syntax parser, which has significant memory and CPU overhead (it has to accept arbitrary expressions in the list). But there's a shortcut around the parser