Additional performance data on Pavel's smb3 multi credit patch series

Steve French smfrench at
Tue Jul 15 22:06:32 MDT 2014

Continuing testing of Pavel's newest SMB3 multicredit patch series,
which significantly improves large file read/write speeds to Samba and
Windows from Linux. For this workload LInux to Linux - SMB3 seems
faster than alternatives for read (copying from the server) but about
the same as NFS for write (copy to server).  Some additional data:

client Ubuntu with 3.16-rc4 and Pavel's patch series, server Fedora 20
(3.14.9 kernel, and Samba server version 4.1.9)

 dd if=/mnt/testfile of=/dev/null bs=50M count=30

testfile is 1.5GB existing file, unmount/mount inbetween each large
file copy to avoid any caching effect on client (although server will
have cached it)

SMB3 averaged 199MB/sec reads (copy from server)
CIFS averaged 170MB/sec reads (copy from server)
NFSv3 averaged 116MB/sec (copy from server)
NFSv4 and v4.1 averaged 110MB/sec (copy from server)

Write speeds (doing dd if=/dev/zero of=/mnt/testfile bs=60M count=25)
were more widely varied but averaged similar speeds for copy to server
for both NFSv3/v4/v4.1 and SMB3 (about 175MB/s)

On Sun, Jul 13, 2014 at 2:23 PM, Steve French <smfrench at> wrote:
> Performance of Pavel's multicredit i/o SMB3 patches continues to look
> good.  Additional informal performance results below comparing cifs
> mounts with smb3 mounts (vers=3.0) with and without Pavel's patch set.
> I plan to do additional testing with large rsize/wsize (default with
> Pavel's code is 1MB).
> 3.16-rc4 (Ubuntu) on client.  Server is Windows 8.1.  Both VMs on same
> host (host disk is fairly fast SSD).
> Copy to server performance increased about 20% percent
> dd if=/dev/zero of=/mnt/targetfile bs=80M count=25
> got similar results with or without conv=fdatasync
> 1st run copying to empty directory, 2nd run copying over targetfile,
> (pattern repeated multiple times) averaging results
> New code (with Pavel's patches)
> ---------------------------------------------
> CIFS 167MB/s
> SMB3 200MB/s
> Existing code (without his patches)
> ------------------------------------------------
> SMB3 166MB/s
> CIFS 164.5MB/s
> For large file reading SMB3 performance with Pavel's patches increased
> 76% over existing SMB3 code
> dd of=/dev/null if=/mnt/targetfile bs=80M count=25
> (mounting and unmounting between attempts to avoid caching effects on
> the client)
> New code (with Pavel's patches)
> ---------------------------------------------
> CIFS 114MB/s
> SMB3 216MB/s
> Existing code (without his patches)
> ------------------------------------------------
> SMB3 123MB/s
> CIFS 110MB/s
> --
> Thanks,
> Steve



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