On Thu, 18 Aug 2011 08:22:44 -0400 (EDT)
Justin Piszcz [off-list ref] wrote:

On Thu, 18 Aug 2011, Justin Piszcz wrote:

quoted

On Thu, 18 Aug 2011, Justin Piszcz wrote:

quoted

On Thu, 18 Aug 2011, J. R. Okajima wrote:

quoted

Justin Piszcz:

quoted

Does anyone know if any kernel supports CIFS w/out crashing? I'd like to
backup some CIFS shares, thanks.


mount -t cifs //w2/x /mnt -o user=user,pass=pass

[  881.388836] CIFS VFS: cifs_mount failed w/return code = -22

	:::

Since it failed mounting, this patch will help you. Although the patch
will fix one bug, there still may exist another problem.

http://marc.info/?l=linux-cifs&m=131345112022031&w=2

Hi,

Latest patch (this one) applied to linux-3.1-rc2 works, at least it mounted
this time and did not instantly crash the kernel!

I also tried the hostname again (and it did not crash the kernel, but it 
failed to mount).

Used the IP and it mounted successfully:
//10.0.0.11/x          28T  5.0T   23T  19% /mnt
//10.0.0.11/y          19T  1.2T   18T   7% /mnt2

It has not crashed yet (which is good), I'll apply this patch to my
production machine and test taking backups of this data and let you know
if it crashes again, thanks!

Justin.

Hello,

It is working but very slowly:

Device eth6 [10.0.1.2] (1/1):
================================================================================
Incoming:                               Outgoing:
Curr: 37.60 MByte/s                     Curr: 0.44 MByte/s
Avg: 4.98 MByte/s                       Avg: 0.09 MByte/s
Min: 0.00 MByte/s                       Min: 0.00 MByte/s
Max: 40.79 MByte/s                      Max: 0.48 MByte/s
Ttl: 1.45 GByte                         Ttl: 26.77 MByte

Over 10GbE the other direction (Linux -> Windows (via Samba)) I get 500MiB/s, 
is CIFS slow?

I'll look into options to tweak the speed but this is very poor speed when 
you have to transfer 5-10TB.  However, it is not crashing anymore, so any 
speed is better than that :)

Justin.

Hi,

Mounting with:
rw,uid=1000,gid=100,mode=0644,rsize=130048,wsize=1048576,credentials=/root/.cifs 
Same speed:
Device eth6 [10.0.1.2] (1/1):
================================================================================
Incoming:                               Outgoing:
Curr: 32.42 MByte/s                     Curr: 0.38 MByte/s
Avg: 30.72 MByte/s                      Avg: 0.39 MByte/s
Min: 0.00 MByte/s                       Min: 0.00 MByte/s
Max: 43.64 MByte/s                      Max: 0.59 MByte/s
Ttl: 20.15 GByte                        Ttl: 261.03 MByte

Thoughts?

Has anyone achieved > 30-40MB/s with CIFS?
This is a 10GbE link (and yes JUMBO frames are enabled on both sides, and 
again, samba from Linux->Windows = 500MB/s)

Justin.

To be clear -- incoming in this case is reads or writes?

Up until 3.0 cifs.ko didn't parallelize writes from a single thread. In
3.0 I added a patchset to increase the allowable wsize and to allow the
kernel to issue writes in parallel.

Reads still suffer from the same problem however. I'm working on a
patchset that should do the same thing for them, but it requires a
fairly substantial overhaul of the receive codepaths.

-- 
Jeff Layton [off-list ref]