Snort mailing list archives
Re: Problems with base and postgresql
From: Frank Knobbe <frank () knobbe us>
Date: Tue, 05 Apr 2005 17:06:29 -0500
On Tue, 2005-04-05 at 15:54 -0400, Michael Stone wrote:
For example, there are a lot of instances of count(*) in the code. mysql shortcuts that operation by keeping a counter, but in postgres that triggers a sequential scan of the table--which can take a while for a large table.
This can be solved by counting an element that is indexed instead of *, for example, if a single index for ip_src exist, count(ip_src) is faster than count(*) as it will to a scan on the index. Also, don't forget about tricks like "limit 1" etc. Queries can, and should be tuned, to each individual database in order to achieve maximum throughput. Perhaps one size does not fit all, and someone might want to create a BASE-pg and BASE-mysql version or something. But since it's open source, everyone is welcome to tweak their own stuff. Postgres performance tuning is borderline to a black-art. But once tuned (server and application)... man... it just rocks. Regards, Frank
Attachment:
signature.asc
Description: This is a digitally signed message part
Current thread:
- Re: Problems with base and postgresql Michael Stone (Apr 04)
- Re: Problems with base and postgresql Alejandro Flores (Apr 04)
- Re: Problems with base and postgresql Michael Stone (Apr 05)
- Re: Problems with base and postgresql Aaron Glenn (Apr 05)
- Re: Problems with base and postgresql Michael Stone (Apr 05)
- Re: Problems with base and postgresql Bamm Visscher (Apr 05)
- Re: Problems with base and postgresql Frank Knobbe (Apr 05)
- Re: Problems with base and postgresql Michael Stone (Apr 05)
- Re: Problems with base and postgresql Alejandro Flores (Apr 04)