Messages in this thread | | | Date | Sun, 6 Apr 2003 11:55:37 -0700 (PDT) | From | dean gaudet <> | Subject | Re: tuning disk on 3ware /performance problem |
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On Sun, 6 Apr 2003, Chuck Ebbert wrote:
> > > > > Is there anything i can do to tune the drives connected to he 3ware > > controller ? (37MB/sec vs 43MB/sec) (and why is the seq. output block > > 65MB/sec on the 3ware vs 41MB/sec on 'ide controllers') > > > Try doing a real test with a 1 GB file on an empty filesystem: > > > # mount /fs && date > # time dd if=/dev/zero of=/fs/file1 bs=128k count=8k
that should be:
time 'dd if=/dev/zero of=/fs/file1 bs=128k count=8k && sync'
otherwise you're not measuring the time it takes to get all the data to disk.
or use lmdd from lmbench, and its built in syncing options.
> # umount /fs && date && mount /fs
or i suppose if you're not looking at the output of "time" and rather hand subtracting the two dates?
-dean
> # time dd if=/fs/file1 of=/dev/null bs=128k > > > I get numbers that disagree with hdparm by a large amount. > > -- > Chuck > I am not a number! > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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