bad NFS/UDP performance

[Claus Guttesen]

On Mon, Sep 29, 2008 at 11:39 AM, Danny Braniss <danny at cs.huji.ac.il> wrote:
>> > it more difficult than I expected.
>> > for one, the kernel date was missleading, the actual source update is the key, so
>> > the window of changes is now 28/July to 19/August. I have the diffs, but nothing
>> > yet seems relevant.
>> >
>> > on the other hand, I tried NFS/TCP, and there things seem ok, ie the 'good' and the 'bad'
>> > give the same throughput, which seem to point to UDP changes ...
>>
>> Can you post the network-numbers?
> [again :-]

Thank you. :-)

Was not shure whether tcp gave you same performance compared to udp or
tcp-performance was stable throughout the same period where udp would
degrade.

>> > Writing 16 MB file
>> >     BS    Count /---- 7.0 ------/ /---- 7.1 -----/
>
> should now read:
>                    /---- Aug 18 ------/  /--- Aug 19 ----/
>> >        1*512  32768 0.16s  98.11MB/s  0.43s 37.18MB/s
>> >        2*512  16384 0.17s  92.04MB/s  0.46s 34.79MB/s
>> >        4*512   8192 0.16s 101.88MB/s  0.43s 37.26MB/s
>> >        8*512   4096 0.16s  99.86MB/s  0.44s 36.41MB/s
>> >       16*512   2048 0.16s 100.11MB/s  0.50s 32.03MB/s
>> >       32*512   1024 0.26s  61.71MB/s  0.46s 34.79MB/s
>> >       64*512    512 0.22s  71.45MB/s  0.45s 35.41MB/s
>> >      128*512    256 0.21s  77.84MB/s  0.51s 31.34MB/s
>> >      256*512    128 0.19s  82.47MB/s  0.43s 37.22MB/s
>> >      512*512     64 0.18s  87.77MB/s  0.49s 32.69MB/s
>> >     1024*512     32 0.18s  89.24MB/s  0.47s 34.02MB/s
>> >     2048*512     16 0.17s  91.81MB/s  0.30s 53.41MB/s
>> >     4096*512      8 0.16s 100.56MB/s  0.42s 38.07MB/s
>> >     8192*512      4 0.82s  19.56MB/s  0.80s 19.95MB/s
>> >    16384*512      2 0.82s  19.63MB/s  0.95s 16.80MB/s
>> >    32768*512      1 0.81s  19.69MB/s  0.96s 16.64MB/s
>> >
>> > Average:                   75.86            33.00

-- 
regards
Claus

When lenity and cruelty play for a kingdom,
the gentler gamester is the soonest winner.

Shakespeare