Re: [PERFORM] optimization ideas for frequent, large(ish) updates in frequently accessed DB?

2004-02-12 Thread Josh Berkus
Marinos, > shared_buffers=10 > (I tried many values, this seems to work well for us - 12GB RAM) > wal_buffers=500 > sort_mem=80 > checkpoint_segments=16 > effective_cache_size=100 > etc. 800MB for sort mem? Are you sure you typed that correctly? You must be counting on not having

[PERFORM] optimization ideas for frequent, large(ish) updates in frequently accessed DB?

2004-02-12 Thread Marinos J. Yannikos
Hi, one of our tables has to be updated frequently, but concurrently running SELECT-queries must also have low latency times (it's being accessed through a web interface). I'm looking for ideas that might improve the interactive performance of the system, without slowing down the updates too m

Re: [PERFORM] Disappointing performance in db migrated from MS SQL Server

2004-02-12 Thread Josh Berkus
Leon, > Hello all. I am in the midst of porting a large web application from a > MS SQL Server backend to PostgreSQL. The migration work is basically > complete, and we're at the testing and optimization phase of the > project. The results so far have been disappointing, with Postgres > perfor

Re: [PERFORM] Disappointing performance in db migrated from MS SQL Server

2004-02-12 Thread Chris Ruprecht
Bruce, my bet is on the limited amount of shared memory. The setup as posted by Leon only shows 80 MB. On a 4 GB database, that's not all that much. Depending on what he's doing, this might be a bottleneck. I don't like the virtual memory strategy of Linux too much and would rather increase thi

Re: [PERFORM] Disappointing performance in db migrated from MS SQL Server

2004-02-12 Thread PC Drew
Please run your largest (worst) queries using EXPLAIN ANALYZE and send in the results so we can see how the queries are being executed & optimized. On Feb 12, 2004, at 11:29 AM, Leon Out wrote: Hello all. I am in the midst of porting a large web application from a MS SQL Server backend to Post

Re: [PERFORM] Disappointing performance in db migrated from MS SQL Server

2004-02-12 Thread Bruce Momjian
Leon Out wrote: > Hello all. I am in the midst of porting a large web application from a > MS SQL Server backend to PostgreSQL. The migration work is basically > complete, and we're at the testing and optimization phase of the > project. The results so far have been disappointing, with Postgres

Re: [PERFORM] Disappointing performance in db migrated from MS SQL

2004-02-12 Thread scott.marlowe
On Thu, 12 Feb 2004, Leon Out wrote: > Hello all. I am in the midst of porting a large web application from a > MS SQL Server backend to PostgreSQL. The migration work is basically > complete, and we're at the testing and optimization phase of the > project. The results so far have been disappo

[PERFORM] Disappointing performance in db migrated from MS SQL Server

2004-02-12 Thread Leon Out
Hello all. I am in the midst of porting a large web application from a MS SQL Server backend to PostgreSQL. The migration work is basically complete, and we're at the testing and optimization phase of the project. The results so far have been disappointing, with Postgres performing queries in a