Re: [PERFORM] Memory usage of writer process
This is postgres 8.4 BTW. It says 2.9Gb of RESIDENT memory, that also seems to be shared. Is this the writer sharing the records it wrote in a shared buffer? PID USER PR NI VIRT RES SHR S %CPU %MEMTIME+ COMMAND 11088 postgres 13 -2 3217m 3.0g 3.0g S0 39.5 0:14.23 postgres: writer process 968 postgres 14 -2 3219m 1.4g 1.4g S0 18.8 4:37.57 postgres: cribq cribq [local] idle 24593 postgres 13 -2 3219m 331m 327m S0 4.3 0:10.12 postgres: cribq cribq [local] idle 26181 postgres 13 -2 3219m 323m 319m S0 4.2 0:06.48 postgres: cribq cribq [local] idle 12504 postgres 14 -2 3219m 297m 293m S0 3.9 0:02.71 postgres: cribq cribq [local] idle 13565 postgres 14 -2 3219m 292m 288m S0 3.8 0:02.75 postgres: cribq cribq [local] idle 623 postgres 13 -2 3219m 292m 287m S0 3.8 0:02.28 postgres: cribq cribq [local] idle On Thu, Aug 13, 2009 at 1:29 PM, Alvaro Herreraalvhe...@commandprompt.com wrote: Alex wrote: The writer process seems to be using inordinate amounts of memory: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 11088 postgres 13 -2 3217m 2.9g 2.9g S 0 38.7 0:10.46 postgres: writer process 20190 postgres 13 -2 3219m 71m 68m S 0 0.9 0:52.48 postgres: cribq cribq [local] idle I am writing moderately large (~3k) records to my database a few times a second. Even when I stop doing that, the process continues to take up all of that memory. Am I reading this right? Why is it using so much memory? shared_buffers? -- Alvaro Herrera http://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc. -- Alex Neth Liivid, Inc www.liivid.com +1 206 499 4995 +86 13761577188 Stephen Leacock - I detest life-insurance agents: they always argue that I shall some day die, which is not so. - http://www.brainyquote.com/quotes/authors/s/stephen_leacock.html -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
Re: [PERFORM] Memory usage of writer process
Alex wrote: The writer process seems to be using inordinate amounts of memory: PID USER PR NI VIRT RES SHR S %CPU %MEMTIME+ COMMAND 11088 postgres 13 -2 3217m 2.9g 2.9g S0 38.7 0:10.46 postgres: writer process 20190 postgres 13 -2 3219m 71m 68m S0 0.9 0:52.48 postgres: cribq cribq [local] idle I am writing moderately large (~3k) records to my database a few times a second. Even when I stop doing that, the process continues to take up all of that memory. Am I reading this right? Why is it using so much memory? shared_buffers? -- Alvaro Herrerahttp://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc. -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
Re: [PERFORM] Memory usage of writer process
On 8/12/09 9:44 PM, Alex a...@liivid.com wrote: The writer process seems to be using inordinate amounts of memory: PID USER PR NI VIRT RES SHR S %CPU %MEMTIME+ COMMAND 11088 postgres 13 -2 3217m 2.9g 2.9g S0 38.7 0:10.46 postgres: writer process 20190 postgres 13 -2 3219m 71m 68m S0 0.9 0:52.48 postgres: cribq cribq [local] idle I am writing moderately large (~3k) records to my database a few times a second. Even when I stop doing that, the process continues to take up all of that memory. Am I reading this right? Why is it using so much memory? It is exclusively using the difference between the RES and SHR columns. So ... Less than ~50MB and likely much less than that (2.9g - 2.9g with rounding error). SHR is the shared memory the process has touched, and is shared amongst all postgres processes. Typically, this maxes out at the value of your shared_buffers setting. Based on the above, I'd wager your shared_buffers setting is 3000MB. If your writer process or any other process has a value for (RES - SHR) that is very large, then be concerned. For example, the second postgres process in the above top output is using about 3MB exclusively, but has touched about 68MB of the shared space, and so it shows up as 68 + 3 = 71m in the RES column. 3MB is not much so this is not a concern. -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
