btrfs kernel workqueues performance regression

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

 



Hi,

I see that btrfs is using kernel workqueues since linux 3.15. After
some tests I noticed performance regressions with fs_mark.

mount options: rw,relatime,compress=lzo,space_cache

fs_mark on Kernel 3.14.9:

# fs_mark  -d  /mnt/btrfs/fsmark  -D  512  -t  16  -n  4096  -s  51200  -L5  -S0
FSUse%        Count         Size    Files/sec     App Overhead
     1        65536        51200      17731.4           723894
     1       131072        51200      16832.6           685444
     1       196608        51200      19604.5           652294
     1       262144        51200      18663.6           630067
     1       327680        51200      20112.2           692769

The results are really nice! compress=lzo performs very good.

fs_mark after upgrading to Kernel 3.15.4:

# fs_mark  -d  /mnt/btrfs/fsmark  -D  512  -t  16  -n  4096  -s  51200  -L5  -S0
FSUse%        Count         Size    Files/sec     App Overhead
     0        65536        51200      10718.1           749540
     0       131072        51200       8601.2           853050
     0       196608        51200      11623.2           558546
     0       262144        51200      11534.2           536342
     0       327680        51200      11167.4           578562

That's really a big performance regression :(

What do you think? It's easy to reproduce with fs_mark.

Thank you.

Best regards,

Morten
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Filesystem Development]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux