Thanks to all for the tips. On Thu, 2005-03-10 at 09:26 -0600, John A Meinel wrote: > How critical is your data? How update heavy versus read heavy, etc are you?
Large, relatively infrequent uploads, with frequent reads. The application is a web front-end to scientific research data. The scientists have their own copy of the data, so if something went really bad, we could probably get them to upload again. > Do you have a way to restore the database if something fails? If > you do nightly pg_dumps, will you survive if you lose a days worth of > transactions? For now, we have access to a terabyte backup server, and the DB is small enough that my sysadmin lets me have hourly pg_dumps for last 24 hours backed up nightly. Veritas is configured to save daily pg_dumps for the last week, a weekly dump for the last month and a monthly version for the last 6 months. > In general I would recommend RAID1, because that is the safe bet. If > your db is the bottleneck, and your data isn't all that critical, and > you are read heavy, I would probably go with RAID1, if you are write > heavy I would say 2 independent disks. I feel that we have enough data safety such that I want to go for speed. Some of the queries are very large joins, and I am going for pure throughput at this point - unless someone can find a hole in my backup tactic. Of course, later we will have money to throw at more spindles. But for now, I am trying gaze in to the future and maximize my current capabilities. Seems to me that the "best" solution would be: * disk 0 partition 1..n - os mounts partition n+1 - /var/lib/postgres/data/pg_xlog * disk 1 partition 1 - /var/lib/postgres/data * Further (safe) performance gains can be had by adding more spindles as such: - first disk: RAID1 to disk 1 - next 2 disks: RAID 0 across the above Do I grok it? Thanks again, -- Karim Nassar Department of Computer Science Box 15600, College of Engineering and Natural Sciences Northern Arizona University, Flagstaff, Arizona 86011 Office: (928) 523-5868 -=- Mobile: (928) 699-9221 ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq