Обсуждение: raid setup for db
Hi I am wondering what stripe size, on a raid 0, is the most suitable for postgres 8.2? I read a performance tutorial by Bruce Momjian and it suggest setting the stripe size to the same block size (as pg uses?) ( http://momjian.us/main/writings/pgsql/hw_performance/index.html ) But I want to check whether I have understood this correctly. Are there any other hot confguration tips I should consider or does anybody have any suggestions for other raid configuration articles? regards thomas
On Wed, May 13, 2009 at 1:51 AM, Thomas Finneid <tfinneid@fcon.no> wrote: > Hi > > I am wondering what stripe size, on a raid 0, is the most suitable for > postgres 8.2? > > I read a performance tutorial by Bruce Momjian and it suggest setting the > stripe size to the same block size (as pg uses?) > ( http://momjian.us/main/writings/pgsql/hw_performance/index.html ) > But I want to check whether I have understood this correctly. > > Are there any other hot confguration tips I should consider or does anybody > have any suggestions for other raid configuration articles? 8k is a pretty small stripe size. If you do anything that needs seq scans, a larger stripe size generally helps. It's probably more important to align the file system's block size to the underlying RAID than to worry about the pg block size too much. Common values that have been posted here running fast for both random and sequential access have been in the 32k to 256k range with some outliers on the high end doing well.
Thomas Finneid wrote: > Hi > > I am wondering what stripe size, on a raid 0, is the most suitable for > postgres 8.2? > Hello Raid 0 for a database? This is a disaster waiting to happen. Are you sure you want to use raid0? regards -- Rafael Martinez, <r.m.guerrero@usit.uio.no> Center for Information Technology Services University of Oslo, Norway PGP Public Key: http://folk.uio.no/rafael/
Dont worry about it, this is just for performance testing. thomas > Thomas Finneid wrote: >> Hi >> >> I am wondering what stripe size, on a raid 0, is the most suitable for >> postgres 8.2? >> > > Hello > > Raid 0 for a database? This is a disaster waiting to happen. > Are you sure you want to use raid0? > > regards > -- > Rafael Martinez, <r.m.guerrero@usit.uio.no> > Center for Information Technology Services > University of Oslo, Norway > > PGP Public Key: http://folk.uio.no/rafael/ > > -- > Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance >