Re: Increase request size for levels other than raid0?

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

 



Mario 'BitKoenig' Holbe <Mario.Holbe@xxxxxxxxxxxxx> wrote:
> I have a raid0 over 4x dm-crypt over 4x raid1 (degraded) over 4 disks
...
> Since request size is a limiting factor for dm-crypt performance, it
> would be great if at least raid1 could also tune itself to the
> underlying queue max_hw_sectors (or at least max_sectors).

Just as a small motivation: eliminating raid1 in the above setup gains
me +50MB/s raw dd-throughput (260MB/s vs. 310MB/s). When a filesystem
(xfs) enters the game, the gain can increase even more - I remember
about 300MB/s streaming read on a pure device-mapper based setup
comparable to mine (same hardware) while I'm now stuck at about 210MB/s.


regards
   Mario
-- 
The opposite of a correct statement is a false statement.
But the opposite of a profound truth may well be another profound truth.
                                                           -- Niels Bohr

--
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


[Index of Archives]     [Linux RAID Wiki]     [ATA RAID]     [Linux SCSI Target Infrastructure]     [Linux Block]     [Linux IDE]     [Linux SCSI]     [Linux Hams]     [Device Mapper]     [Device Mapper Cryptographics]     [Kernel]     [Linux Admin]     [Linux Net]     [GFS]     [RPM]     [git]     [Yosemite Forum]


  Powered by Linux