Re: syncfs slower than without syncfs

[Stefan Priebe - Profihost AG <s.priebe@profihost.ag>]

Am 07.11.2012 10:41, schrieb Stefan Priebe - Profihost AG:
> Hello list,
>
> syncfs is much slower than without syncfs to me.
>
> If i compile latest ceph master with wip-rbd-read:
>
> with syncfs:
> rand 4K:
>    write: io=1133MB, bw=12853KB/s, iops=3213, runt= 90277msec
>    read : io=1239MB, bw=14046KB/s, iops=3511, runt= 90325msec
> seq 4M:
>    write: io=37560MB, bw=423874KB/s, iops=103, runt= 90738msec
>    read : io=103852MB, bw=1151MB/s, iops=287, runt= 90237msec
>
> without syncfs:
> rand 4K:
>    write: io=3733MB, bw=42459KB/s, iops=10614, runt= 90039msec
>    read : io=6018MB, bw=68446KB/s, iops=17111, runt= 90038msec
> seq 4M:
>    write: io=51204MB, bw=577328KB/s, iops=140, runt= 90820msec
>    read : io=150320MB, bw=1666MB/s, iops=416, runt= 90228msec
>
> I thought syncfs should boost the performance.

Fixed - my chroot env with glibc syncfs support didn't had the libcrypto 
installed and it isn't in the control dependencies. Now with libcrypto i 
get the same results as without syncfs.

Stefan