Re: is there a bandwidth limit per file?

Michael <mic@xxxxxxx> · Tue, 13 May 2008 21:48:37 +0200

Hello!

Sorry for late answer but, i was on travel until sunday. I tried with 

Ubuntu Live CD but still with similiar limit. So, I decided to upgrade 

to Gigabit Interface (Switch & NICs).

Here, the results for the case someone is curious.

Now I get around 160MBit on average from and to the server. This does 

not change when copying several files in parallel. With NETIO around 

250MBit (linx-win) and 500MBit (win-win) are possible. I guess 20MB/s is 

what i can get with this slow computer and Samba.

Thank you, Jeremy for the fast and good support,
   Michael

Jeremy Allison schrieb:

On Fri, Apr 25, 2008 at 12:20:19AM +0200, Michael wrote:

Hello Everybody!

I set up a fileserver:
   - Pentium II, 350 Mhz,
   - 256MB RAM,
   - Intel Fast Ethernet PCI
   - VIA-SATA Controller
   - 2x500GB SATA HDD RAID 1
   - Debian 4, Samba 3
   - Samba set up in user shares mode without special options, but with
the suggested optimizations

Clients:
   - Windows XP Prof SP2

So far it works fine. I can read and write files without problem. But my
bandwith seems to be limited somehow. When i copy one file i get a
nearly constant transfer rate of about 6.8 MB/s (read and write).
Do i copy two files in parallel i get a total transfer rate of about
10MB/s (again for read and write)
with 3 files it is even around 11MB/s. Why i can't reach this transfer
rate with just one file? It is the same from both windows pc.

I benchmarked my network around 11.5MB/s are reached using netio
(Win-Win,Win-Debian).
The HDDs are reaching 60MB/s with hdparm -t /dev/sd?

I search for such an issue, but didn't find something useful. I looked into 

the documentation, but didn't find some hints for that issue.

How can i find the bootleneck in the system?

I'd guess the problem is the Windows redirector only
allowing one outstanding 64k read/write request on
the wire at a time. This is a known problem with
XP. To test is this is the case, try using smbclient
from another Linux box to write a file and see
if the throughput rises. We allow up to max mux
(protocol limit) outstanding requests on the
wire.

Jeremy.

--
To unsubscribe from this list go to the following URL and read the
instructions:  https://lists.samba.org/mailman/listinfo/samba