Then you should set it to 100 or so. It helps to keep the number of connections down to something reasonable. On Wed, May 21, 2008 at 12:06 AM, Andy Dale <andy.dale@xxxxxxxxx> wrote: > Hi, > > I currently have max_connections set to 300, however if i think about it we > will never have that many connections (more like 50 - 100 at most). > > Cheers, > > Andy > > 2008/5/20 Scott Marlowe <scott.marlowe@xxxxxxxxx>: >> >> On Tue, May 20, 2008 at 8:14 AM, Andy Dale <andy.dale@xxxxxxxxx> wrote: >> > Hi, >> > >> > I am currently trying to tweak Postgresql 8.1, to improve the overall >> > performance of the database. I have read over the following >> > page/artical >> > http://www.powerpostgresql.com/PerfList/, however at the moment (not for >> > much longer hopefully) my hands aree tied when it comes to altering the >> > kernel parameters, and thus allocating more shared buffers. >> > >> > I have read over the rest of the artical and adjusted some of the other >> > values mentioned. The values I have altered are: >> > >> > work_mem = 33554 # min 64, size in KB >> >> Depending on how many connections you're handling and how much memory >> you have, this might be a little large, but it's not terrible. Make >> sure you aren't running your machine low on spare memory, as this can >> cause the machine to start swapping and make it run slower. >> >> > maintenance_work_mem = 33554 # min 1024, size in KB >> > max_fsm_pages = 100000 # min max_fsm_relations*16, 6 >> > bytes >> > each >> > >> > vacuum_cost_delay = 50 # 0-1000 milliseconds >> >> Maybe a little high. most people find that 10 is just fine to keep >> vacuum from slamming your I/O bandwidth. >> >> > wal_buffers = 64 # min 4, 8KB each >> > commit_delay = 0 # range 0-100000, in >> > microseconds >> > commit_siblings = 50 # range 1-1000 >> >> Setting a short commit delay may allow for more siblings to get >> committed together. >> >> > effective_cache_size = 33333000 # typically 8KB each >> > >> > autovacuum = on # enable autovacuum >> > subprocess? >> > autovacuum_naptime = 30 # time between autovacuum runs, in >> > secs >> > autovacuum_vacuum_threshold = 400 # min # of tuple updates before >> > vacuum >> > autovacuum_analyze_threshold = 100 # min # of tuple updates before >> > analyze >> > autovacuum_vacuum_scale_factor = 0.4 # fraction of rel size before >> > vacuum >> > autovacuum_analyze_scale_factor = 0.2 # fraction of rel size before >> > analyze >> > >> > Is it ok to have these settings with increasing the amount of shared >> > buffers >> > ? >> >> Sure. What's your max connections set to? > >
