samba - Jun 2010 - Samba Transfer Efficiency

Afternoon all,
I'm running a transfer setup as follows:
A -> B -> C - fairly simple, B initiates a transfer from A to C - B is a 
vital intermediary as it bridges two otherwise seperate networks.
All machines have onboard Gigabit ethernet, A+B are connected via 
Crossover and B->C is connected by very fast switch (i.e. all 
connections should be able to use the full gig if they wanted to)
I see an average of about 23-25% usage in both the crossover (A->B) and 
the connection (B->C) - are there any tricks you can recommend for me to 
speed up my transfers?
Box A is the box running Samba 3.5.1-42.el5
Box B is Win Server 2003
Box C is a NAS (BSD)
I've found a lot of what seems to be outdated information online like 
changing my SNDBUF to 8192 so I thought i'd drop an email to the list 
for more up to date information.
Many thanks,
Henri

Henri Cook wrote:
> Afternoon all,
> I'm running a transfer setup as follows:
> A -> B -> C - fairly simple, B initiates a transfer from A to C - B
is a
> vital intermediary as it bridges two otherwise seperate networks.
> All machines have onboard Gigabit ethernet, A+B are connected via 
> Crossover and B->C is connected by very fast switch (i.e. all 
> connections should be able to use the full gig if they wanted to)
> I see an average of about 23-25% usage in both the crossover (A->B) and 
---
	That's about the maximum I see for reads.  I get about 30MB/s for
writes from a Win7 client to a samba server. 


	I had faster using 9K jumbo packets, BUT, I had too many multimedia
drop-outs on Win7 (never a problem on WinXP).  So I scaled back to the
standard 1500 byte packets and slower speeds.  The Windows client stacks
aren't that fast, in my experience. 


Make sure your tcp stack is tuned on your linux server.  My distro had set my
max TCP window size and memory usage set way lower than needed for good Gigabit
performance.