[linux-cifs-client] Re: sendmsg blocking with sendtimeout vs. non-blocking

[Shirish Pargaonkar]

Steve,

Here is a run against a samba share

usr/src/dbench/dbench-3.04 # ./dbench -s -S -t 5s -D /mnt/smb_n -c client.txt 1
dbench version 3.04 - Copyright Andrew Tridgell 1999-2004

Running for 5 seconds with load 'client.txt' and minimum warmup 1 secs
1 clients started
   1        12     0.00 MB/sec  warmup   1 sec
   1        12     0.00 MB/sec  warmup   2 sec
   1        12     0.00 MB/sec  warmup   3 sec
   1        12     0.00 MB/sec  warmup   4 sec
   1        12     0.00 MB/sec  warmup   5 sec
   1        12     0.00 MB/sec  warmup   6 sec
   1        12     0.00 MB/sec  warmup   7 sec
   1        12     0.00 MB/sec  warmup   8 sec
   1        12     0.00 MB/sec  warmup   9 sec
   1        12     0.00 MB/sec  warmup  10 sec
   1        12     0.00 MB/sec  warmup  11 sec
   1        12     0.00 MB/sec  warmup  12 sec
   1        12     0.00 MB/sec  warmup  13 sec
   1        12     0.00 MB/sec  warmup  14 sec
   1        12     0.00 MB/sec  warmup  15 sec
   1        12     0.00 MB/sec  warmup  16 sec
   1        12     0.00 MB/sec  warmup  17 sec
   1        12     0.00 MB/sec  warmup  18 sec
   1        12     0.00 MB/sec  warmup  19 sec
   1        12     0.00 MB/sec  warmup  20 sec
   1        12     0.00 MB/sec  warmup  21 sec
   1        12     0.00 MB/sec  warmup  22 sec
   1        12     0.00 MB/sec  warmup  23 sec
   1        12     0.00 MB/sec  warmup  24 sec
   1       102     2.82 MB/sec  execute   1 sec
   1       163     2.42 MB/sec  execute   2 sec
   1       223     2.24 MB/sec  execute   3 sec
   1       232     1.75 MB/sec  execute   4 sec
   1       232     1.40 MB/sec  cleanup   5 sec
   1       232     1.16 MB/sec  cleanup   6 sec
   1       232     1.00 MB/sec  cleanup   7 sec
   1       232     0.87 MB/sec  cleanup   8 sec
   1       232     0.78 MB/sec  cleanup   9 sec
   1       232     0.70 MB/sec  cleanup  10 sec
   1       232     0.63 MB/sec  cleanup  11 sec
   1       232     0.58 MB/sec  cleanup  12 sec
   1       232     0.54 MB/sec  cleanup  13 sec
   1       232     0.50 MB/sec  cleanup  14 sec
   1       232     0.47 MB/sec  cleanup  15 sec
   1       232     0.44 MB/sec  cleanup  16 sec
   1       232     0.41 MB/sec  cleanup  17 sec
   1       232     0.39 MB/sec  cleanup  18 sec
   1       232     0.37 MB/sec  cleanup  19 sec
/bin/rm: cannot remove directory
`/mnt/smb_n/clients/client0/~dmtmp/COREL': Directory not empty
   1       232     0.35 MB/sec  cleanup  20 sec

Throughput 1.39629 MB/sec (sync open) (sync dirs) 1 procs


And here is against a Windows XP share

:/usr/src/dbench/dbench-3.04 # ./dbench -s -S -t 5s -D /mnt/smb_r -c
client.txt 1
dbench version 3.04 - Copyright Andrew Tridgell 1999-2004

Running for 5 seconds with load 'client.txt' and minimum warmup 1 secs
1 clients started
   1       132     3.01 MB/sec  execute   1 sec
   1       207     2.68 MB/sec  execute   2 sec
   1       284     2.61 MB/sec  execute   3 sec
   1       357     2.51 MB/sec  execute   4 sec
   1       418     2.40 MB/sec  cleanup   5 sec
   1       418     2.01 MB/sec  cleanup   6 sec
   1       418     1.72 MB/sec  cleanup   7 sec
   1       418     1.51 MB/sec  cleanup   8 sec
   1       418     1.34 MB/sec  cleanup   9 sec
   1       418     1.20 MB/sec  cleanup  10 sec
   1       418     1.10 MB/sec  cleanup  11 sec
   1       418     1.00 MB/sec  cleanup  12 sec
   1       418     0.93 MB/sec  cleanup  13 sec
   1       418     0.86 MB/sec  cleanup  14 sec
   1       418     0.80 MB/sec  cleanup  15 sec
   1       418     0.75 MB/sec  cleanup  16 sec
   1       418     0.71 MB/sec  cleanup  17 sec
   1       418     0.67 MB/sec  cleanup  18 sec
   1       418     0.63 MB/sec  cleanup  19 sec
   1       418     0.60 MB/sec  cleanup  20 sec
   1       418     0.57 MB/sec  cleanup  21 sec
   1       418     0.55 MB/sec  cleanup  22 sec
   1       418     0.52 MB/sec  cleanup  23 sec
   1       418     0.50 MB/sec  cleanup  24 sec
/bin/rm: cannot remove directory
`/mnt/smb_r/clients/client0/~dmtmp/PARADOX': Directory not empty
   1       418     0.49 MB/sec  cleanup  24 sec

Throughput 2.40957 MB/sec (sync open) (sync dirs) 1 procs


And the testrun still running with your patch.

Regards,

Shirish

On Fri, Oct 24, 2008 at 9:23 AM, Steve French <smfrench at gmail.com> wrote:
>
>
> On Fri, Oct 24, 2008 at 7:53 AM, Neil Horman <nhorman at redhat.com> wrote:
>>
>>  The correct solution is to read data out of the socket into a temporary
>> buffer that you allocate in the cifs code, and loop repetatively calling
>> recv[msg|from] until such time as the entire message has been read.
>>
>>
> That is what the cifs code does in cifs_demultiplex_thread.
>
> Shirish,
> If we can verify that performance does not appear to be impacted (e.g. some
> dbench runs against remote server and also against localhost/samba)  when
> removing the few lines of code in (cifs's) ipv4_connect in which cifs sets
> sndbuf/rcvbuf (we never set them in the case fortunately) - then I will
> remove those lines immediately (and I am ok with not having a mount option
> to turn off the autotuning ie revert to old behavior)
>
>
>
> --
> Thanks,
>
> Steve
>