Hi Neil,
On Mon, 18 Aug 2008, Neil Brown wrote:
http://www.metsahovi.fi/~jwagner/10g-tests/pmp/linux-raid-1.txt
you appear to be doing the write tests to the three small arrays in
series, one after the other.
You need to do them in parallel to find the aggregate bandwidth of the
system.
i.e. run
sudo /usr/bin/time dd if=/dev/zero of=/dev/md0 bs=1024k count=48000 &
sudo /usr/bin/time dd if=/dev/zero of=/dev/md1 bs=1024k count=48000 &
sudo /usr/bin/time dd if=/dev/zero of=/dev/md2 bs=1024k count=48000 &
all at once in the background. What does that produce?
Sorry, I forgot to mention this in the .txt file: all the three tests
were in fact running in parallel, just on different xterm terminals. The
.txt is a copypaste from the three terminals.
When I used '&' backgrounding the results were the same.
But let's redo it, for completeness:
oper@abidal:~$ sudo /usr/bin/time dd if=/dev/zero of=/dev/md0 bs=1024k count=48000 &
[1] 13283
oper@abidal:~$ sudo /usr/bin/time dd if=/dev/zero of=/dev/md1 bs=1024k count=48000 &
[2] 13286
oper@abidal:~$ sudo /usr/bin/time dd if=/dev/zero of=/dev/md2 bs=1024k count=48000 &
[3] 13288
48000+0 records in
48000+0 records out
50331648000 bytes (50 GB) copied, 218.485 s, 230 MB/s
0.07user 147.77system 3:38.50elapsed 67%CPU (0avgtext+0avgdata 0maxresident)k
48inputs+98304008outputs (1major+520minor)pagefaults 0swaps
48000+0 records in
48000+0 records out
50331648000 bytes (50 GB) copied, 218.206 s, 231 MB/s
0.05user 145.51system 3:38.20elapsed 66%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+98304008outputs (0major+521minor)pagefaults 0swaps
48000+0 records in
48000+0 records out
50331648000 bytes (50 GB) copied, 218.895 s, 230 MB/s
0.06user 137.92system 3:38.89elapsed 63%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+98304008outputs (0major+520minor)pagefaults 0swaps
Kind regards,
- Jan
--
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
