Re: Disappointing performance in db migrated from MS SQL

Поиск
Список
Период
Сортировка
От scott.marlowe
Тема Re: Disappointing performance in db migrated from MS SQL
Дата
Msg-id Pine.LNX.4.33.0402170816001.30371-100000@css120.ihs.com
обсуждение исходный текст
Ответ на Re: Disappointing performance in db migrated from MS SQL  (matt@ymogen.net)
Список pgsql-performance
On Fri, 13 Feb 2004 matt@ymogen.net wrote:

> > Josh, the disks in the new system should be substantially faster than
> > the old. Both are Ultra160 SCSI RAID 5 arrays, but the new system has
> > 15k RPM disks, as opposed to the 10k RPM disks in the old system.
>
> Spindle speed does not correlate with 'throughput' in any easy way.  What
> controllers are you using for these disks?

This is doubly so with a good RAID card with battery backed cache.

I'd bet that 10k rpm drives on a cached array card will beat an otherwise
equal setup with 15k rpm disks and no cache.  I know that losing the cache
slows my system down to a crawl (i.e. set it to write thru instead of
write back.) comparitively speaking.


В списке pgsql-performance по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: Slow response of PostgreSQL
Следующее
От: "Todd Fulton"
Дата:
Сообщение: long running query running too long