Well , i have tested the disk with a new tester i have written. it seems that the ata driver causes the high cpu and not raid. On 11/21/05, Raz Ben-Jehuda(caro) <raziebe@xxxxxxxxx> wrote: > What sort of a test is it ? what filesystem ? > I am reading concurrently 50 files . > Are you reading one file , several files ? > > On 11/21/05, Guy <bugzilla@xxxxxxxxxxxxxxxx> wrote: > > > -----Original Message----- > > > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > > > owner@xxxxxxxxxxxxxxx] On Behalf Of Raz Ben-Jehuda(caro) > > > Sent: Monday, November 21, 2005 9:47 AM > > > To: Guy > > > Cc: Linux RAID Mailing List > > > Subject: Re: comparing FreeBSD to linux > > > > > > fetching from a disk a random block of 1 MB is aproximately > > > 20MB/s for a sata disk ( randomly , all over the disk and over a file > > > system). > > > god help us if the cpu what that slow. > > > > If your CPU load is 90% at 20MB/sec then you have a problem. > > > > I get about 56MB per sec on my filesystem which is on a RAID5. > > The CPU load is less than 50% > > I have a P3-500MHz 2 CPU system. VERY OLD! > > > > I have Linux 2.4.31. I don't know if the newer 2.6 is better or not. > > > > Guy > > > > > > > > On 11/21/05, Guy <bugzilla@xxxxxxxxxxxxxxxx> wrote: > > > > > -----Original Message----- > > > > > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > > > > > owner@xxxxxxxxxxxxxxx] On Behalf Of Raz Ben-Jehuda(caro) > > > > > Sent: Sunday, November 20, 2005 6:50 AM > > > > > To: Linux RAID Mailing List > > > > > Subject: comparing FreeBSD to linux > > > > > > > > > > I have evaluated which is better in terms cpu load when dealing with > > > raid. > > > > > FreeBSD vinum's or linux raid. > > > > > When i issued a huge amount of io's read to linux raid i got 93% cpu > > > > > load ( 7% idle), > > > > > while i having 10% cpu load ( 90% idle ) in the freebsd. > > > > > > > > Maybe a silly question... But is it 9.3 times faster under Linux? :) > > > > That would explain the 9.3 times increase in CPU load. > > > > > > > > It is important that you are comparing the CPU load at the same disks > > > rate, > > > > or at least factor in the disk rate. > > > > > > > > Guy > > > > > > > > > > > > > > I need to switch to linux from freebsd. I am using in linux 2.6.6 > > > kernel . > > > > > is problem is a known issue in linux , is it fixed ? > > > > > > > > > > -- > > > > > Raz > > > > > - > > > > > To unsubscribe from this list: send the line "unsubscribe linux-raid" > > > in > > > > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > > > > > - > > > > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > > > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > > > > > > > > > > -- > > > Raz > > > - > > > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > - > > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > > -- > Raz > -- Raz - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
