Yan Li wrote: >> Please could you try if patch here helps and doesn't cause performance degradation? >> http://www2.kernel.org/pub/linux/kernel/people/agk/patches/2.6/2.6.25/dm-crypt-add-cond_resched.patch >> > > Will the result of testing a Debian 2.6.24-etchnhalf.1-amd64 kernel > (very near a vanilla kernel) be of same value? Since the data on some > other drives on this server is important so I dare not try 2.6.25-rc > on it. > patch just adds cond_resched(), problem is the same in all recent kernel I think. just for 2.6.24 kernel patch need to be slighly modified (see below) > Following is my test plan, comments are welcomed: > > Test command: > # dd if=/dev/zero of=/dev/mapper/open_device bs=500M count=10 > (this server has 2G memory) > bonnie++ test or something like that is more appropriate, but for this problem is dd test enough > The command will be run for 3 times, and average speed of last two > runs will be taken as result score. > > flush caches between tests or simple luksClose & luksOpen + mount device between test runs > Dm-crypt LUKS Encryption scenarios: > aes-cbc-essiv:sha256, keysize 128 > aes-xts-plain, keysize 256 > aes-xts-plain, keysize 512 > > I will compare the speed of all above 3 encryption scenarios, with and > without the patch. > > Patch for 2.6.24 kernel Add cond_resched() to prevent stuck in big bio processing. Signed-off-by: Milan Broz <mbroz@xxxxxxxxxx> --- drivers/md/dm-crypt.c | 1 + 1 file changed, 1 insertion(+) Index: linux-2.6.24.3/drivers/md/dm-crypt.c =================================================================== --- linux-2.6.24.3.orig/drivers/md/dm-crypt.c 2008-02-26 01:20:20.000000000 +0100 +++ linux-2.6.24.3/drivers/md/dm-crypt.c 2008-03-01 16:46:24.000000000 +0100 @@ -374,6 +374,7 @@ static int crypt_convert(struct crypt_co break; ctx->sector++; + cond_resched(); } return r; -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
