Hi,
Eyal Lebedinsky wrote:
I noticed that my 3-disk RAID was syncing at about 40MB/s, now that I
added a fourth disk it goes at only 20+MB/s. This is on an idle machine.
3*40=120
4*20=80
Individually, each disk measures 60+MB/s with hdparm.
And concurrent hdparms? Or some dd's concurrently?
kernel: 2.6.13 on ia32
Controller: Promise SATAII150 TX4
Disks: WD 320GB SATA
Q: Is this the way the raid code works? The way the disk-io is managed? Or
could it be due to the SATA controller?
You can isolate the performance drop with some dd's. Maybe this card is
in a pci32/33mhz and you're hitting the pci bus' limits? (120~130MB/sec).
Regards,
Nuno Silva
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