reading to cifs mount point is slow

student975 · 2011-03-27 05:27:57

If I use smbclient and do 'get somefile', I get a speed up to 100MB/s (Gigabit LAN is in use). If I read from cifs mount point , I get 10-12MB/s only. I have tried both 'cp' and 'dd' (last one with bs=8M and of=/dev/null). I have tried both directly mounting and via autofs with the same result. autofs string looks like this:

media   -fstype=cifs,iocharset=utf8,noperm,noatime,rw,user=uuuuuu,password=ppppppp ://nas/media

Where to dig in? What is that big difference between smbclient and cifs-mounting? Are there another ways to mount samba share and get all traffic LAN is able to transmit?

student975 · 2011-03-27 05:35:22

Well, I must to add writing to cifs mount point ('cp' or 'dd') is as fast as 'put' with smbclient (also up to 100MB/s). Only reading is infected.

student975 · 2011-03-27 07:19:41

OK, friends, waiting for your answer I have found not absolutely perfect, but very good way to rise speeds. I have

- added 'directio' to mount options (and this is a main trick), and
- added to /etc/modprobe.d/ a file with 'options cifs CIFSMaxBufSize=130048' string.

Now (with dd) I have 98MB/s reading from samba and 75MB/s writing to samba (with real file operations on samba size and /dev/zero and /dev/null on client size). It is slightly smaller than with smbclient (110MB/s and 88MB/s), but, I hope, acceptable.

Nevertheless I'll be still happy to hear about that last secret resolving trick!

student975 · 2011-03-27 21:54:25

Heh.. Nowbody uses shares in the Arch World...

Now I'm on selecting an appropriate two-panels file manager to work with cifs. On the way, rough throughputs in relative values are listed below (with fastest smbclient beeing equal to 1.0):

1.0 smbclient
0.8 dd
0.7 mucommander, worker
0.5 cp, qtFM
0.3 mc
0.1 KDE

To tell the truth, I'm completely frustrated.. I don't understand such terrible difference

How do we all still alive with such throughput??

Last edited by student975 (2011-03-28 05:03:29)

Wittfella · 2011-03-28 10:28:23

Hello student975,

I guess maybe people aren't jumping in here because they are not really seeing the problem. Your getting 100MB/s? Wow! Thats about the theoretical limit of a gigabit lan isn't it? I'm not sure how you are doing that, I have never got close to transferring across a lan at near the limit. Hell, I don't get those speeds on my internal hard drive!

I'm not sure why smbclient is faster than mounting a cifs share. Are you connecting to ntfs shares with ntfs-3g?

student975 · 2011-03-28 11:02:13

Wittfella wrote:

I guess maybe people aren't jumping in here because they are not really seeing the problem. Your getting 100MB/s? Wow!

Yes, smbclient read at 110MB/s, and dd "read' at 98MB/s. Last one - via mount.cifs.

The main question is: why file managers are such different? And, say, especially for you - why mucommander (java application) is ~1.5 faster rather qtFM is? Not saying about mc and, especially, about KDE..

Wittfella wrote:

I'm not sure why smbclient is faster than mounting a cifs share.

Probably smbclient and mount.cifs use different API.

Wittfella wrote:

Are you connecting to ntfs shares with ntfs-3g?

I'm connecting from AL workstation (i5 760, 4GB DDR3, ...) to self-made NAS (also AL, Celeron E3200, 2GB DDR3, and so on) via NetGear SG105E gigabit switch. Both computers' motherboards (both Gygabyte) have 1Gb LAN ports. iperf shows 950Mbit/s in one direction, and 740+740Mbit/s in duplex.

voyager6868 · 2011-04-16 04:46:53

I have the same problem. I think part of the problem is that a lot of people running Linux must have not-so-fast hardware

My RAID-0 SSDs can read at ~400MB/s and my RAID-0 regular 500GB hard drives can read at ~170MB/s, so the bottleneck is my 1Gbit NIC when copying between two machines.

Anyway, it's unfortunate that this type of copying isn't more optimized in Linux. If I have some time, maybe I'll write a nice GUI that does fast copies. Otherwise, smbclient seems to do the job.

student975 · 2011-04-16 07:32:24

voyager6868 wrote:

Anyway, it's unfortunate that this type of copying isn't more optimized in Linux. If I have some time, maybe I'll write a nice GUI that does fast copies. Otherwise, smbclient seems to do the job.

Do you mean experiments with different file managers as I have descibed above? Have you own such measurements?

Last edited by student975 (2011-04-16 07:33:06)

voyager6868 · 2011-05-04 06:31:48

I haven't tried all the file managers, but I have used Nautilius, mounting with cifs, and smbclient, and only smbclient has a decent speed.

Nautilus max is 60MB/s, and mounting cifs with the default options gives me less than 10MB/s. On the other hand, smbclient gives me around 110MB/s, which is near the max for a 1 Gbit NIC.

kokoko3k · 2011-05-04 07:05:30

Well, probably related, Just vote for that bug, dolphin is a pig for mounted shares:
https://bugs.kde.org/show_bug.cgi?id=255306

jumperfly · 2011-05-04 18:42:49

I'm having the exact same issue as described by student975. Unfortunately I don't have a solution to offer but thought I should say you are not alone .

Your two suggestions (directio and CIFSMaxBufSize) were very helpful, improving my speed by about 3 or 4 times. Unfortunately it's still half the speed of smbclient! I'm a Gentoo user on kernel 2.6.37. Approx speeds (I'm on a 100Mb network through homeplug adapters hence the slower speeds):
* smbclient 7.5 MB/s
* cifs mount cp (directio and CIFSMaxBufSize): 3.5 MB/s
* cifs mount cp (directio): 2.5 MB/s
* cifs mount cp (with default options): <1MB/s

If anyone has a solution to make cifs mounts copy as fast as smbclient please share!

Not using KDE, so not related to the above for me.

kokoko3k · 2011-05-05 07:11:47

I tried directio in the past, while it make a huge difference in speed, it has a drawback.

i have a mounted cifs share from win1 to lin1 with directio (mountpoint /mnt/cifs1)
the mounted cifs share is shared from lin1 via sshfs to lin2 (say (mountpoint /mnt/cifs1_sshfs1)
when i access /mnt/cifs_1_sshfs1 from lin2 and try to copy a large file, it is truncated without any error message.

without directio, it works flawlessly.

Wittfella · 2011-06-03 12:58:48

Hey, twl just posted this in another thread, might be related to this problem.

student975 · 2011-06-04 00:08:13

Wittfella wrote:

Hey, twl just posted this in another thread, might be related to this problem.

I have this maximum (110 MiB/s) without that trick, but have measured with Linux smbclient only (haven't windows installation anywhere around). At any case - thanks for the trick.

kokoko3k · 2011-06-05 01:16:18

Wittfella wrote:

Hey, twl just posted this in another thread, might be related to this problem.

No luck, cifs totally ignores any directive in smb.conf

student975 · 2011-06-05 11:11:00

I guess cifs driver doesn't know abour smb.conf at all - that trick is for server side.

kokoko3k · 2012-01-30 08:27:27

It is an old thread, *i know*
but if someone jumps here with problems, he has to know that on linux >=3.2 specifiyng an rsize at mount time now gave lower transfer speeds, and modprobing cifs with CIFSMaxBufSize parameter isn't that relevant anymore.
http://permalink.gmane.org/gmane.linux.kernel.cifs/4221

student975 · 2012-01-30 09:41:34

@kokoko3k

For your valuable information the thread can not be "old" Thanks!

Arch Linux

#1 2011-03-27 05:27:57

reading to cifs mount point is slow

#2 2011-03-27 05:35:22

Re: reading to cifs mount point is slow

#3 2011-03-27 07:19:41

Re: reading to cifs mount point is slow

#4 2011-03-27 21:54:25

Re: reading to cifs mount point is slow

#5 2011-03-28 10:28:23

Re: reading to cifs mount point is slow

#6 2011-03-28 11:02:13

Re: reading to cifs mount point is slow

#7 2011-04-16 04:46:53

Re: reading to cifs mount point is slow

#8 2011-04-16 07:32:24

Re: reading to cifs mount point is slow

#9 2011-05-04 06:31:48

Re: reading to cifs mount point is slow

#10 2011-05-04 07:05:30

Re: reading to cifs mount point is slow

#11 2011-05-04 18:42:49

Re: reading to cifs mount point is slow

#12 2011-05-05 07:11:47

Re: reading to cifs mount point is slow

#13 2011-06-03 12:58:48

Re: reading to cifs mount point is slow

#14 2011-06-04 00:08:13

Re: reading to cifs mount point is slow

#15 2011-06-05 01:16:18

Re: reading to cifs mount point is slow

#16 2011-06-05 11:11:00

Re: reading to cifs mount point is slow

#17 2012-01-30 08:27:27

Re: reading to cifs mount point is slow

#18 2012-01-30 09:41:34

Re: reading to cifs mount point is slow

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