[Samba] Nagging performance issues with Vista

[Jeremy Allison]

On Fri, Jun 22, 2007 at 11:29:16AM +1000, Andrew Cook wrote:
> Hi All,
> 
> I've got some performance issues with Samba and Vista that I just can't 
> seem to figure out. Googling and fiddling has all been in vain up until 
> now, so I'm not sure what I can do other than wait for Samba 4, but 
> maybe someone here can find something I've missed.
> 
> First off, the server is an Athlon 64 1.8GHz running Gentoo 2006.1, 
> tested with both Samba 3.0.24 and 3.0.25a. Gigabit network is handled by 
> the onboard nForce controller, and it's got a software RAID 5 setup that 
> has been running fine for months.
> 
> The client is a dual core Windows box with a PCI-Express gigabit card. 
> Netperf pegs the network at 100Mbytes/sec, so there's no problems there. 
> Transfers via FTP on both Windows XP and Vista work out around about 
> 55Mbytes/sec consistently, and SMB transfers under Windows XP also top 
> out around 50-55Mbytes/sec, which seems to be the limit of the I/O on 
> the client.
> 
> Vista however, no matter what I do, will not read from Samba shares at 
> any more than around 5Mb/s when copying with Explorer. I timed a few 
> different file copies between XP and Vista, and it's consistently ten 
> times slower every time. Write speeds seem a lot better (20-30Mb/s). 
> This happens with both Samba 3.0.24 and 3.0.25a. I've tried with the VFS 
> readahead both on and off. I've tried with NetBIOS over TCP/IP both on 
> and off. It's worth noting that if I use the copy command via the 
> command prompt, read speeds jump to around 8-9Mb/s, but it's still 
> pretty poor.

Ah - the readahead issue. Try using 3.0.25 with the vfs readahead
module.

Jeremy.