smbmount read/write block size stuck at 4k

[Dan Singletary]

Dag,

So, I tried using mount.cifs instead of smbmount (same as using 'cifs' 
instead of 'smbfs' in fstab)... same performance issue it looks like- 
I'll have to look at packet dumps to be sure it's the same "stuck at 4k 
block reads" problem that I see with smbfs.  I looked up bugs on 
bugzilla and it seems like development is no longer taking place on 
smbfs, since cifs has replaced it.   I have run into a symlink issue 
with cifs but I can work around that.... still, there is no performance 
increase with cifs (that I've seen).

-Dan

Dag Wieers wrote:
> 
> 
> Yes, I've reported the same problem a week ago. Both the smb client 
> as the cifs client have this problem, on 2.4 and 2.6 kernels. I know
> Steve French is working on it since recently. You may have better
> luck in getting a technical explanation from the linux-cifs-client
> ml.
> 
> Even though we all need a solution right now, this thread looks 
> promising:
> 
> http://lists.samba.org/archive/linux-cifs-client/2004-December/000543.html
> 
> 
> 
> On Wed, 8 Dec 2004, Dan Singletary wrote:
>> When using smbmount to mount a share from WinXP, I observed 
>> less-than-optimal throughput when copying a file from the remote 
>> share to a local disk.  Observation of the protocol dialog with 
>> Ethereal revealed that smbmount was making read requests for 4k 
>> bytes at a time. Similar observation of protocol dialog between two
>>  WinXP boxes showed that the typical read request was for 64k.
>> 
>> I then tried to use smbclient to 'get' the file, and again observed
>>  4k SMB read requests.  I found that using the '-b <buffersize>' 
>> option with smbclient is effective in REDUCING the buffer size as 
>> small as 1 byte (reflected in Ethereal showing 1 byte SMB read 
>> requests), however I am unable to use '-b' to increase the read 
>> requests beyond 4k.
>> 
>> Why does smbmount/smbclient only read  data at 4k per block?  This 
>> results in horribly poor performance (~4 MBytes/sec) on a gigabit 
>> network that should permit transfer rates that challenge the speed 
>> of the disk drives involved...
> 
> Kind regards, --   dag wieers,  dag at wieers.com, 
> http://dag.wieers.com/   -- [all I want is a warm bed and a kind word
>  and unlimited power]