On Sunday October 12, duke@mastre.com wrote: > I've been playing around with linux Software RAID it for a day or so and > have been testing all types of scenarios, like simulating disk failures, > rebuilds, etc. And I've run into some problems. On top of this, I have > some thoughts on the subject (imagine that! ;) that I will post here. > So, here we go: > > The test system I am running this on is: > Supermicro P4SCE-based server > Pentium 4 2.4GHz 800MHz FSB > - HyperThreading Enabled > - RedHat Linux 9, stock 2.4.20-8smp kernel > 1GB PC3200 ECC RAM (2x512) > 2 x Maxtor 5A250J0 250GB 5400RPM HD > - connected to sep channels, in UDMA5 mode > - one is hda, the other hdd (CD-ROM is hdc) > snip > > Now, besides the fact that I _know_ the hardware is much faster than a > measly 12MB/s, when I monitor mdrecoveryd and raid1d via top, > mdrecoveryd occasionally goes over 2.0% to 3.1%, but usually lingers at > 1.9%. raid1d stays at under 1% most of the time. There is nothing else > actively running on the system (see ps ax and output at end). So what > gives? Why are my disks only mustering 12MB/s when they should instead > be maxing out the system to try to achieve my 100MB/s goal? Does the > "124k window" have something to do with this? 100MB/sec might be the speed of the interface, but it certaintly isn't the speed of the drive. My 15000 RPM SCSI drives do around 30MB/sec, so your 5400RPM drives are doing OK at 12MB/sec. NeilBrown - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
