On Sat, 28 Jun 2003, Alex Verbitsky wrote: > What kernel did you use for testing? Those two machines are running 2.4.21, and saw similar results under 2.4.20. > upgrading firmware to 7.6 - the same. I'll try this next week when I'm at the office, and see if it does anything. > As a conclusion, seems that RH9's kernel (and maybe some other kernels?) are broken. Using a self built kernel, so who knows. > Also, did you tweaked max-readahead/min-readahead params? > doing this: > echo 256 > /proc/sys/vm/max-readahead > echo 128 > /proc/sys/vm/min-readahead > increased my sequental read from 58 MB/s to 80 MB/s (at expense of CPU > usage - from 22% to 36%). Haven't touched those, testing that now. Yup, seeing about a 10-15% increase for the most part, and a little more cpu load, which is't a problem, as I've got spare cpu to spare, even with the gzip going. Can't very accurately test the system as I can't just init 1 it and go test from here. > Also you did not report your RAM size. if you have 512 MB, your > results are not very accurate because some amount of writes is > cached. 256 meg in each machine. > I highly recommend you to upgrade - though i did not notice any > performance gains, it contains new improved CLI utility with online > array create/delete commands, and also better support RH8. I have one machine running 7.6 already, and didn't notice anything useful to me, besides being able to call up the alarms from the cli, which I track in the syslog anyways. If I have a drive failure, I have to power down the machine anyways, so online create/delete doesn't bother me much. > MD> The 7000-2 and 7500-4's in raid1 work quite nicely. The 7500-4 in raid5 > MD> actually lags the system for 3-5 seconds when doing a lot of disk i/o. > MD> Feels like working on a p120 with DMA shut off, to be honest. > What do you mean by this? I did not notice anything like this, though i > use it for sequental i/o mainly. > if your i/o is highly random, then 3ware acceleration (R5 fusion) is > not working and you should receive something like 5-10 MB/s. Likely that, as if I'm ungzip'ing say a 3 gig file, and then go to log in, doing even an ls will take a few seconds to come up. Mike - 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
