What is the highest hard drive read/write speed you were able
to achieve by entire disk mirroring or striping?
yuri at rawbw.com
Mon May 18 20:29:52 UTC 2009
Wojciech Puchar wrote:
>> I am seeing 85MB/s as a speed of a single Hitachi 1TB HD.
>> How high can you go by mirroring or striping 2, 3, 4 harddrives?
> mirroring - the same, just with 2 processes reading both can get the
> bandwidth. make sure you use -s high enough (like 1048576) doing
> gmirror label
> stripping - the same, or 2,3,4 times, depends how you configure.
> for highest transfer and lowest concurrency (you mostly read huge
> files with one process) - use small stripe size.
> for lowest transfer (=1 disk) and highest concurency - use very huge
> stripe size like 512MB, so simply different process reading different
> things can hit different drives, but each I/O isn't spread.
So if I will put 6 hard drives with stripping each of them is 85MB/s (in
the beginning sectors) I will get 6X85MB/s=4.08Gb/s?
Is it reasonable to expect this kind of speed? Something tells me that
there will be some other factors like bus speed that would potentially
limit the speed in such case.
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