On Thu, 08 Jan 2004 15:11:09 +0100, Jens Frank wrote:
2*80G 7.2kRPM,
8MB cache SATA drives
SATA RAID controller (we could run raid 0 or 1 for redundancy or
speed - since a webserver ought not hit the disk all that much,
I think redundancy is more important)
Looking at pliny and larousse, from the numbers I've been told,
their disks are highly busy, bi and bo are very high in vmstat.
This should be the current cache- it could be switched off once the Squids
are working. I even don't see a need for Apache logging- the logging is
done on the Squids. The only potentially disk-accessing operation would be
serving images which will get picked up by the squids as well.
My proposal for the Apaches is heaps of Cpu, single ordinary drive and
enough memory to prevent any swapping. And some more of them. We don't
need high reliability as long as we have enough of them.
> SATA vs. SCSI -- SCSI is theoretically faster,
although many say that
> the practical difference is minimal. SCSI is theoretically more
> reliable, but with 2 SATA drives in RAID redundant configuration, this
> is a very minor issue?
I might be wrong, but the only gain it having a big disk might be a faster
start up time ;-)
You'd need heartbeat for the load balancers,
anyway.
Doing it on the squids would just save two boxes.
Why three squids? Two would be enough, and even one should be able
to handle the load if the other one fails.
+1
Should the DB backup machine really have a different
sizing from the
active machine? From what I've seen brion say geoffrin is rather
idle, so perhaps yes. On the other hand side, administration would
be easier when having two identical boxes, or at least same CPU
family. A small Altus 1000 E dual Opteron (single Opterons are
not offered by penguincomputing?) with 2 GB RAM (ECC!), 2*80 disk, no
CDROM, is at 2,810 $. We could probably get away with two of these
for web serving instead of four, and save 2 units of rackspace.
+1 again ;-)
Gabriel Wicke