2011/4/22 Cédric Villemain <cedric.villemain.debian@xxxxxxxxx>: > 2011/4/22 Tory M Blue <tmblue@xxxxxxxxx>: >> On Fri, Apr 22, 2011 at 4:03 AM, Cédric Villemain >> <cedric.villemain.debian@xxxxxxxxx> wrote: >>> 2011/4/21 Tory M Blue <tmblue@xxxxxxxxx>: >>>> On Thu, Apr 21, 2011 at 7:27 AM, Merlin Moncure <mmoncure@xxxxxxxxx> wrote: >>>>> On Thu, Apr 21, 2011 at 3:28 AM, Tory M Blue <tmblue@xxxxxxxxx> wrote: >>>> >>>>>> Fedora 12 >>>>>> 32gig memory, 8 proc >>>>>> postgres 8.4.4, slony 1.20 >>>>>> 5 gigs of swap (never hit it!) >>>>> >>>>> curious: using 32/64 bit postgres? what are your postgresql.conf >>>>> memory settings? >>>>> >>>>> merlin >>>>> >>>> >>>> 32bit >>>> 32gb >>>> PAE kernel >>>> >>>> # - Checkpoints - >>>> checkpoint_segments = 100 >>>> max_connections = 300 >>>> shared_buffers = 2500MB # min 128kB or max_connections*16kB >>>> max_prepared_transactions = 0 >>>> work_mem = 100MB >>>> maintenance_work_mem = 128MB >>>> fsync = on >>>> >>> >>> I didn't understand what value you set for vm.overcommit parameters. >>> Can you give it and the values in /proc/meminfo, the interesting one >>> are "Commit*" ? >>> >>> If you have strict rules(overcommit=2), then your current kernel >>> config may need some love : the commit_limit is probably too low >>> because you have a small swap partition. One way is to change : >>> vm.overcommit_ratio. >>> By default it should be something like 21GB (0.5*32+5) of >>> commit_limit, and you probably want 32GB :) >>> >>> Maybe you have some minor changes in your install or application usage >>> and you just hit the limit. >> >> Thanks Cedric >> >> the sysctl vm's are >> >> # 04/17/2011 to keep overcommit memory in check >> vm.overcommit_memory = 2 >> vm.overcommit_ratio = 0 >> >> CommitLimit: 4128760 kB >> Committed_AS: 2380408 kB > > Are you sure it is a PAE kernel ? You look limited to 4GB. > > I don't know atm if overcommit_ratio=0 has a special meaning, else I > would suggest to update it to something like 40% (the default), but default being 50 ... > 60% should still be safe (60% of 32GB + 5GB) > >> >> >> Ya I do think my swap space is biting us, (but again just starting to >> grasp that my swap space which has not grown with the continued >> addition of memory). I am just not starting to learn that the swap >> does need to be properly sized whether it's being used or not. I >> figured it would use the swap and it would run out, but sounds like >> the system takes the size into consideration and just decides not to >> use it. >> >> I appreciate the totally no postgres responses with this. >> >> Thanks >> Tory >> > > > > -- > Cédric Villemain 2ndQuadrant > http://2ndQuadrant.fr/ ; PostgreSQL : Expertise, Formation et Support > -- Cédric Villemain 2ndQuadrant http://2ndQuadrant.fr/ ; PostgreSQL : Expertise, Formation et Support -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
