Re: [ADMIN] Speed problem

Terry Mackintosh wrote:

> Note, with a table that big your swap space should be on a physically
> differant hard drive (from the db) so that the db and the swap are not
> always fighting for the use of the drive heads.
>

Terry,

    I have a rather large database as well (> 2 Meg of tuples). I thought
my system was souped up enough: PII/400 MHz (100 MHz bus) 256 Meg SDRAM,
18 Gig SCSI harddrive, Red Hat Linux 5.1. However, my swap space (512
Meg) is on the same harddrive as the database (albeit on a separate
partition). It sounds like you are saying that this is a no-no.

    The database runs quite fast except with processes involving repetitive
inserts or updates. With each successive update in a continuous process,
the speed drops (almost like an exponentially decreasing process). Plus,
when this happens, I can't really use the computer that runs the
database because it is soooooo slow. When I run top, the computer is
using all 256 Meg of memory and going about 30-40 meg into swap space.
From what you've suggested, this 30-40 meg of swap is also competing
with the database trying to write to the harddrive (since they are using
the same head).

    If I put in a second drive exclusively for the swap space, could this
increase my speed? Or, would it be better to invest in more RAM so that
the job wouldn't need to use any swap space at all?

Thanks.
-Tony