David C. Rankin wrote:
Sandy Drobic wrote:
Sandy Drobic wrote:
David C. Rankin wrote:
/dev/dm-0: Timing cached reads: 3432 MB in 2.00 seconds = 1716.32 MB/sec Timing buffered disk reads: 194 MB in 3.02 seconds = 64.27 MB/sec
The Software RAID penalty -- virtually non-existent as far as hdparm is concerned. That is probably due to getting rid of the pci bus. Here's a hardware raid (3ware 9650SE, 5 x 750 GB Seagate SATA2):
mordor:~ # hdparm -tT /dev/mapper/system-var
/dev/mapper/system-var: Timing cached reads: 13236 MB in 2.00 seconds = 6626.75 MB/sec Timing buffered disk reads: 1130 MB in 3.00 seconds = 376.05 MB/sec
Here's the data of my old server (old pci hardware raid, 3 x 18 GB SCSI):
/dev/rd/c0d0p3: Timing cached reads: 298 MB in 2.00 seconds = 148.70 MB/sec Timing buffered disk reads: 62 MB in 3.02 seconds = 20.56 MB/sec
Quite a difference. (^-^)
Are those 5 750G drives are in RAID0/RAID5 ? That is incredible disk performance.
Yes, it's a RAID5. Though write performance is much less. Most of the time this is theoretical data with no real life worth. In most cases it is more important how fast many small files are written or read. Still, since the controller is working in write-back mode, write performance is acceptable in my case. -- Sandy List replies only please! Please address PMs to: news-reply2 (@) japantest (.) homelinux (.) com -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org