[PERFORM] large object write performance

2015-10-08 Thread Bram Van Steenlandt
Hi, I use postgresql often but I'm not very familiar with how it works internal. I've made a small script to backup files from different computers to a postgresql database. Sort of a versioning networked backup system. It works with large objects (oid in table, linked to large object), which

Re: [PERFORM] large object write performance

2015-10-08 Thread Bram Van Steenlandt
Op 08-10-15 om 13:21 schreef Graeme B. Bell: First the database was on a partition where compression was enabled, I changed it to an uncompressed one to see if it makes a difference thinking maybe the cpu couldn't handle the load. It made little difference in my case. My regular gmirror par

Re: [PERFORM] large object write performance

2015-10-08 Thread Bram Van Steenlandt
ing all the time or do you start it before this test? Perhaps check if any background tasks are running when you use postgres - autovacuum, autoanalyze etc. Graeme Bell On 08 Oct 2015, at 11:17, Bram Van Steenlandt wrote: Hi, I use postgresql often but I'm not very familiar with how it

Re: [PERFORM] large object write performance

2015-10-08 Thread Bram Van Steenlandt
Op 08-10-15 om 13:37 schreef Graeme B. Bell: Like this ? gmirror (iozone -s 4 -a /dev/mirror/gm0s1e) = 806376 (faster drives) zfs uncompressed (iozone -s 4 -a /datapool/data) = 650136 zfs compressed (iozone -s 4 -a /datapool/data) = 676345 If you can get the complete tables (as in the imag

Re: [PERFORM] large object write performance

2015-10-08 Thread Bram Van Steenlandt
Op 08-10-15 om 14:10 schreef Graeme B. Bell: On 08 Oct 2015, at 13:50, Bram Van Steenlandt wrote: 1. The part is "fobj = lobject(db.db,0,"r",0,fpath)", I don't think there is anything there Re: lobject http://initd.org/psycopg/docs/usage.html#large-objects &quo

Re: [PERFORM] large object write performance

2015-10-08 Thread Bram Van Steenlandt
Op 08-10-15 om 15:10 schreef Graeme B. Bell: http://initd.org/psycopg/docs/usage.html#large-objects "Psycopg large object support *efficient* import/export with file system files using the lo_import() and lo_export() libpq functions.” See * I was under the impression they meant that the l