Hi,
There have been several requests (from more than one person, or just from one person) for 15k spindle drives. Is that a universal consensus? I find it hard to imagine that faster drives is really pertinent, because just about any problem that can be solved with faster drives can be solved better with more ram?
In theory: yes. But if more RAM or faster UPM are better should be tested, this belongs to the kind of application.
Don't you/we have a dealer who allows to test this on a new server? This could help us to proof our suggestions instead of speculating.
RAID 10? That's what geoffrin had, and it was sweet. But RAID 5 would give more disk space, right?
Yes. RAID 10 gives you 50% of the hard disc capacity while RAID 5 gives you 66%. That sounds not too much difference but it is :-) 8 drives of 150 GB -> 1200 GB gross capacity. RAID 10: 600 GB net capacity. RAID 5: about 792 GB net capacity. That's more than one extra hard drive for "free".
RAID 10 is a bit faster than RAID 5.
I would recommend two or three spare hard drives, not only one. If one's dying in the RAID and the only hotspare drives begins to rebuild the data (which could take quite a long time) and before someone is able to replace the broken one a second hard drive gets corrupted then the RAID is lost. This is of no importance if someone is 24/7 near the server room.
What are our disk requirements for the db server? Let's be generous with ourselves here. But, also let's think about whether disk space needs might in some cases be better handled by a big slow cheap SATA storage server?
SATA-RAIDs are as fast as SCSI-RAIDs concerning the sustained read benchmarks but not when accessing random data - this is what I measured for our firm here.
BTW: I don't know siliconmechanics (and can't reach their website now) but I was very content with Fujitsu-Siemens Primergy servers. We're running a lot of them. No, I don't have stock options or something like that from them and we don't sell them (we don't sell something computer related at all).
YMMV.
Sorry for my bad English, I'm not a native speaker.
Regards Götz