NFS over LAGG / lacp poor performance

[Steven Hartland]

----- Original Message ----- 
From: "Gerrit Kühn" <gerrit.kuehn at aei.mpg.de>
To: "Steven Hartland" <killing at multiplay.co.uk>
Cc: <freebsd-net at freebsd.org>
Sent: Friday, April 25, 2014 4:52 PM
Subject: Re: NFS over LAGG / lacp poor performance


> On Fri, 25 Apr 2014 15:55:29 +0100 "Steven Hartland"
> <killing at multiplay.co.uk> wrote about Re: NFS over LAGG / lacp poor
> performance:
>
> SH> Run top then enable system processes (shift+S) and threads (shift+H)
> SH> then disable idle process display (z) if your seeing significant CPU
> SH> usage to the igb interrupt handlers try reducing the number.
>
> Hm, I'm a bit unsure what I see here:
>
> ---
> last pid: 71026;  load averages:  0.36,  0.37, 0.27
> up 18+03:14:21  17:48:02
> 295 processes: 5 running, 259 sleeping, 31 waiting
> CPU:  0.0% user,  0.0% nice,  0.0% system,  0.0% interrupt,  100% idle
> Mem: 3596K Active, 59M Inact, 11G Wired, 900K Cache, 1236M Buf, 1019M Free
> Swap: 16G Total, 14M Used, 16G Free
>
>  PID USERNAME   PRI NICE   SIZE    RES STATE   C   TIME   WCPU COMMAND
>    0 root       -16    0     0K  2672K -       2 272:01  0.00% kernel{zio_write_issue_}
>    0 root       -16    0     0K  2672K -       0 271:55  0.00% kernel{zio_write_issue_}
>    0 root       -16    0     0K  2672K -       3 271:54  0.00% kernel{zio_write_issue_}
>    0 root       -16    0     0K  2672K -       1 271:52  0.00% kernel{zio_write_issue_}
> 1455 root        20    0  9912K   472K rpcsvc  2 173:53  0.00% nfsd{nfsd: master}
> 1455 root        20    0  9912K   472K rpcsvc  0 166:37  0.00% nfsd{nfsd: service}
> 1455 root        20    0  9912K   472K rpcsvc  0 164:25  0.00% nfsd{nfsd: service}
> 1455 root        20    0  9912K   472K rpcsvc  3 163:06  0.00% nfsd{nfsd: service}
>   12 root       -92    -     0K   496K WAIT    1 155:36  0.00% intr{irq262: igb1:que}
> [...]
> ---
>
>
> The irq-igb1 clibs to top every now and then (always less than 1% cpu
> usage though), but there is never much cpu usage shown for any task.
> However, the overall load is significant. What might the system be doing?

Thats not your issue then.

    Regards
    Steve