James Robinson wrote:
Users are primarily, if not stupid, ignorant. They will read the absolute
minimum needed to achieve a goal and little else. I say this with the
utmost respect, because I and probably everyone else on this group is
guilty of the same thing. So, the "preferred" installation procedure, i.e.
the one with the easy to follow directions, should showcase features the
user should know, and leave the user in a good place. IMHO, the user's
database on one volume and pg_xlog on another is a better starting place.
Yes, that is generally the case (prefer pg_xlog on separate spindle), but no
need to *forcibly* overcomplicate things if the box has only one spindle,
or if they have only one single RAID'd partition configured. We should
continue to err on the side of keeping the path to a functional system
nice and simple, yet still offering superb functionality. Oracle gets this
wrong. pg_autovacuum is another good step in this direction.
In the age of inexpensive RAID, tablespaces have more or less lost their relevance regarding performance. pgsql's philosophy respects this by leaving the storage work up to the OS and disk subsystem. Even having the xlog on a different spindle won't help too much; you'll probably be better off if you stuff all your spindles in one raid on most systems. For worse, splitting two disks into separate storage areas to have xlog separated would degrade safety for very little performance gain. So the advise is: one disk, no alternative. 2 to 20 disks: use a single raid. more disks: examine your access patterns carefully before you believe you can do the job better than your raid controller.
This leaves table spaces as a mere administrative feature, many (most) installations will happily live without that.
Regards, Andreas
---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives?
http://archives.postgresql.org
