Re: [PERFORM] Postgresql performance degrading... how to diagnose the root cause

2013-03-29 Thread Guillaume Cottenceau
Franck Routier writes: >> http://wiki.postgresql.org/wiki/Show_database_bloat > How do I interpret the output of this query ? Is 1.1 bloat level on a > table alarming, or quite ok ? I am not very used to this, but I'd start by comparing the top result in your established DB against the top resul

Re: [PERFORM] Postgresql performance degrading... how to diagnose the root cause

2013-03-29 Thread Jeff Janes
On Fri, Mar 29, 2013 at 7:20 AM, Franck Routier wrote: > Hi, > > I have a postgresql database (8.4) running in production whose performance > is degrading. > There have been substantial improvements in performance monitoring in newer versions, so using 8.4 limits your options. > There is no si

Re: [PERFORM] how to help the planner

2013-03-29 Thread Igor Neyman
Marty, When you change from/join collaps_limit pay attention to Genetic Query Optimizer settings, I believe by default it's "on" (geqo = on). Specifically look at geqo_threshold parameter (default is 12). AFAIK, if you don't have intensions to use Genetic Query Optimizer, geqo_threshold parame

Re: [PERFORM] Postgresql performance degrading... how to diagnose the root cause

2013-03-29 Thread Franck Routier
Hi, I don't know that tcp-b does tpcb.jar is a java implementation of the http://www.tpc.org/tpcb/ benchmark. It is not particularly representative of my workload, but gives a synthetic, db-agnostic, view of the system performance. We use it to have quick view to compare differents servers (dif

Re: [PERFORM] [OT] linux 3.10 kernel will improve ipc,sysv semaphore scalability

2013-03-29 Thread Andrea Suisani
Hi On 03/26/2013 07:59 PM, Shaun Thomas wrote: On 03/26/2013 08:04 AM, Andrea Suisani wrote: TPS: 100 users: 1257.21 (vanilla)2805.06 (v3 patchset) 400 users: 1437.57 (vanilla)2664.67 (v3 patchset) 800 users: 1236.89 (vanilla)2750.73 (v3 patchset) Wow, I like the look of that.

Re: [PERFORM] Postgresql performance degrading... how to diagnose the root cause

2013-03-29 Thread Guillaume Cottenceau
Franck Routier writes: > Hi, > > I have a postgresql database (8.4) running in production whose > performance is degrading. > There is no single query that underperforms, all queries do. > Another interesting point is that a generic performance test > (https://launchpad.net/tpc-b) gives mediocre

Re: [PERFORM] Postgresql performance degrading... how to diagnose the root cause

2013-03-29 Thread Julien Cigar
On 03/29/2013 15:20, Franck Routier wrote: Hi, Hello, I have a postgresql database (8.4) running in production whose performance is degrading. There is no single query that underperforms, all queries do. Another interesting point is that a generic performance test (https://launchpad.net/tp

[PERFORM] Postgresql performance degrading... how to diagnose the root cause

2013-03-29 Thread Franck Routier
Hi, I have a postgresql database (8.4) running in production whose performance is degrading. There is no single query that underperforms, all queries do. Another interesting point is that a generic performance test (https://launchpad.net/tpc-b) gives mediocre peformance when run on the databa