Re: Linux Software RAID 5 Performance Optimizations: 2.6.19.1: (211MB/s read & 195MB/s write)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Justin Piszcz wrote:
> RAID 5 TWEAKED: 1:06.41 elapsed @ 60% CPU
>
> This should be 1:14 not 1:06(was with a similarly sized file but not the
> same) the 1:14 is the same file as used with the other benchmarks.  and to
> get that I used 256mb read-ahead and 16384 stripe size ++ 128
> max_sectors_kb (same size as my sw raid5 chunk size)

max_sectors_kb is probably your key. On my system I get twice the read 
performance by just reducing max_sectors_kb from default 512 to 192.

Can you do a fresh reboot to shell and then:
$ cat /sys/block/hda/queue/*
$ cat /proc/meminfo
$ echo 3 > /proc/sys/vm/drop_caches
$ dd if=/dev/hda of=/dev/null bs=1M count=10240
$ echo 192 > /sys/block/hda/queue/max_sectors_kb
$ echo 3 > /proc/sys/vm/drop_caches
$ dd if=/dev/hda of=/dev/null bs=1M count=10240


Thanks!

--
Al

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux