W liście z pon, 17-01-2005, godz. 16:51, Hans Kristian Rosbach pisze: 

[...]

Actually I have managed to get about 30-40% higher throughput with just
a little hacking on the code that selects what disk to use.

Problem is
-It selects the disk that is closest to the wanted sector by remembering
 what sector was last requested and what disk was used for it.
-For sequential reads (sucha as hdparm) it will override and use the
 same disk anyways. (sector = lastsector+1)

I gained a lot of throughput by alternating disk, but seek time was
roughly doubled. I also tried to get smart and played some with the
code in order to avoid seeking both disks back and forth wildly when
there were two sequential reads. I didn't find a good way to do it
unfortunately.

What about the special case where whole disks are mirrored? 
Then there is no need for selecting disks other than round-robin,
because the heads should be in similar positions (except for rebuild
situation).

I will be more than happy to give up partitions to get better
performance instead. I have two disks, so raid 1+0 is not an option.

Could you please reconsider releasing your patch?

Best regards, Janusz
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