SMB performance much lower than FTP

Boyce, Nick nick.boyce at
Tue Nov 27 12:30:02 GMT 2001

[caution: I'm basically a lurker/luser on this list, and it's highly
possible you Samba Team folks shouldn't pay much attention to my ramblings

On 27.Nov.2001 David Collier-Brown and/or Louis Caron said :

> I have a colleague seeing a very odd behavior with copies done
> from a pc client to either a Samba or a Sun "Cascade" SMB server.  
> The SMB copies are roughly ten times slower than ftp (!)
> Before we set up a testing process, can anyone
> suggest why SMB would be orders of magnitude slower
> than FTP on large transfers?

This may be completely irrelevant, but there seems to have been an issue
with the "write raw" feature for some Samba releases now, such that *some*
Unix flavours need the counter-intuitive setting "write raw = no" to achieve
maximum speed.

See my posting to comp.protocols.smb with the subject "Samba Speed Problem
With Digital Unix Solved !" in October 2000 for my 2 cents in respect of
Digital Unix, and someone else's followup in respect of SCO Unixware.

[I apologise about the above URL - I know of no way to get a short URL from

When I set the parameter to "no" I saw an approx 8 times speed-up on PC -->
server writes;  with server --> PC the problem doesn't exist (for me
anyway).  I posted a few times about the problem until I found my solution -
almost nobody bit, but I saw enough other postings from people with slow
PC-to-server speed and acceptable server-to-PC speed to realise it wasn't
just me and my weirdo Digital Unix system :-)

Don't know what the score is with Sun/Solaris systems tho'.

Hope this helps.

Nick Boyce
EDS Southwest Solution Centre, Bristol, UK

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