Mikael Carneholm wrote:
Your numbers seem quite ok considering the number of disks. We also get a 256Mb battery backed cache module with it, so I'm looking forward to testing the write performance (first using ext3, then xfs). If I get the enough time to test it, I'll test both raid 0+1 and raid 5 configurations although I trust raid 0+1 more. And no, it's not the cheapest way to get storage - but it's only half as expensive as the other option: an EVA4000, which we're gonna have to go for if we(they) decide to stay in bed with a proprietary database. With postgres we don't need replication on SAN level (using slony) so the MSA 1500 would be sufficient, and that's a good thing (price wise) as we're gonna need two. OTOH, the EVA4000 will not give us mirroring so either way, we're gonna need two of whatever system we go for. Just hoping the MSA 1500 is reliable as well... Support will hopefully not be a problem for us as we have a local company providing support, they're also the ones setting it up for us so at least we'll know right away if they're compentent or not :)
If I'm reading the original post correctly, the biggest issue is likely to be that the 14 disks on each 2Gbit fibre channel will be throttled to 200Mb/s by the channel , when in fact you could expect (in RAID 10 arrangement) to get about 7 * 70 Mb/s = 490 Mb/s.
Cheers Mark
