Still no solution after 5 months(!) - Transfer speed problem

Mayers, Philip J p.mayers at ic.ac.uk
Wed Dec 20 13:00:46 GMT 2000 

<offtopic>
There are problems with certain 3Com switches not working with certain 3Com
network cards (1100s with VLT enabled on any port and 905b or c's - also,
IIRC, 630s with STP enabled). The new Cisco 3500s are nice, but they take an
age to boot.

The 3Com edge switches are foulness beyond belief - we have 300 of them. The
1000s and 3000s are absolutely apalling, and the 11/3300s little better -
the SNMP capability is undocumented, unless you happen to be using Transcend
(which is no longer supported) and the 3300FX has problems with gigabit
autonegotiation. The new SuperStack IIIs aren't even supported by
Transcend... <sigh>
</offtopic>

In any case - it doesn't sound like a network layer problem to me. And this
is 

Since you're on a hubbed network, take a network sniff of the entire
transaction, both working and not-working, and I'll take a look at them.

Regards,
Phil

+----------------------------------+
| Phil Mayers, Network Support     |
| Centre for Computing Services    |
| Imperial College                 |
+----------------------------------+  

-----Original Message-----
From: Greg Dickie [mailto:greg at discreet.com]
Sent: 20 December 2000 12:04
To: Anders C. Thorsen
Cc: samba-technical at us5.samba.org; Kenichi Okuyama; infernix; Welsh,
Armand
Subject: Re: Still no solution after 5 months(!) - Transfer speed
problem




Not in my experience, I run our whole infrastructure on 3COM switches with a
bunch of different equipment and in my experience they always negoticiate a
good connection, I have recently worked with Cisco Cat 65's and they suck
for
that. Cisco may be good at routing but I'll never buy their switches. Of
course
this is digressing......

Greg

On 19-Dec-00 Anders C. Thorsen wrote:
> On Tue, Dec 19, 2000 at 08:34:00PM -0500, Greg Dickie wrote:
>> 
>> 
>> If you are using Cisco equipment verify the settings on both ends. CISCO
>> does NOT autonegociate well at all!
> 
> The same goes for many 3Com Switches as well. Actually, sometimes 
> (bad firmware), it might force Full duplex on a half duplex
> negotiated connection. Giving _bad_ transfer rates.
> 
> --Anders
>  
>> Greg
>> 
>> 
>> On Tue, 19 Dec 2000, Welsh, Armand wrote:
>> 
>> > Date: Tue, 19 Dec 2000 11:27:59 -0800
>> > From: "Welsh, Armand" <armand.welsh at sscims.com>
>> > To: 'infernix' <infernix at infernix.nl>,
>> >      Kenichi Okuyama <okuyamak at dd.iij4u.or.jp>
>> > Cc: samba-technical at us5.samba.org
>> > Subject: RE: Still no solution after 5 months(!) - Transfer speed
>> >     problems  (oplocks?) with Samba 2.0.7 and Win2K Pro
>> > 
>> > I had a similar problem, I too, used this logic.  All the workstation
in
>> > the
>> > office using windows98 worked fine.  Windows NT/2000 workstations did
not
>> > work correctly.  They were all too slow.  I tried everything.  The
>> > solution
>> > for me, was that I was overlooking something.  The NICs.  All the
>> > workstation had Compaq NIC, as were default installed in them, except
the
>> > winNT/2000 boxes.  Thos machines had 3COM 3c509B/C NICs, and those were
>> > the
>> > nics having a problem.  I could do telnet/ftp/http all quickly, but
lotus
>> > notes, and samba were very, very, very slow.  I assumed the samba thing
>> > was
>> > a timing issue with the way I had samba configured, and that notes was
a
>> > problem, with how lotus programmed their sockets.  I was wrong... dead
>> > wrong...
>> > 
>> > What the problem turned out being, is that the Compaq NICs and the 3Com
>> > NIC
>> > don't play well together, with large data packets, or even potentially,
>> > fragmented packets.  Upon further investigation, I discovered, that by
>> > simply replacing my server's NIC with a 3C509B/C (actually, it was the
>> > euqivalent server version of the NIC), I was now able to access the
data
>> > quickly.  It was that simple.    Now a new problem does exist.  The
>> > server,
>> > now has timing issues when talking to some the other compaq servers,
that
>> > still had compaq NICs in them, and thus authentications would fail to
the
>> > shares on occasions.  I replaced all the servers' compaq NICs with the
>> > 100Mbit server NIC from 3COM, and the problem is now gone.
>> > 
>> > -> -----Original Message-----
>> > -> From: infernix [mailto:infernix at infernix.nl]
>> > -> Sent: Tuesday, December 19, 2000 10:29 AM
>> > -> To: Kenichi Okuyama
>> > -> Cc: samba-technical at us5.samba.org
>> > -> Subject: Re: Still no solution after 5 months(!) - Transfer speed
>> > -> problems (oplocks?) with Samba 2.0.7 and Win2K Pro
>> > -> 
>> > -> 
>> > -> Hi,
>> > -> 
>> > -> > information. According to your test, Windows98 is faster 
>> > -> than Win2k,
>> > -> > right? Then, which device drivers are you using for you 
>> > -> '3com 3c905C
>> > -> > NIC', on each OS? Is it from Microsoft, or is it from 3Com?
>> > -> 
>> > -> This is only partially true. Both OSes are very fast with 
>> > -> FTP. Only Samba is
>> > -> slow on Win2K. This simplifies the problem, because you can 
>> > -> be sure that:
>> > -> 
>> > -> 1) There is no ovbious misconfiguration in the hardware settings
>> > -> 2) This is not a Win2K/Win9x TCP/IP thing (otherwise it 
>> > -> would affect FTP
>> > -> too)
>> > -> 3) There is no change in the smb.conf and therefore it is 
>> > -> not evidently
>> > -> influenced by the Samba configuration file.
>> > -> 4) The server is apparently not to blame since it works fine 
>> > -> in Windows 98.
>> > -> 
>> > -> I tried both OSes with the Windows drivers and the 3Com 
>> > -> drivers. Made no
>> > -> difference.
>> > -> 
>> > -> > If no packets were lost, then run smbd with large number of debug
>> > -> > options ( like... 5 or 6 ... I usually use 10 ), and see 
>> > -> the list of
>> > -> > requests. It might simply that since Win2k is newer version of
>> > -> > Windows, they might be simply sending lots of nasty request (^^;).
>> > -> 
>> > -> I already did that. The logs are retrievable:
>> > -> http://www.infernix.nl/samba/sambalogs.infernix.tgz. Some 
>> > -> parts of these log
>> > -> files were already looked into, as shown in my posting. I 
>> > -> explained some
>> > -> other details there too.
>> > -> 
>> > -> > Run Samba server normally, and than look at your machine's load
>> > -> > average using vmstat ( or anything is okey ), especially CPU load.
>> > -> > Are you having enough CPU power? are you having enough Memory?
>> > -> 
>> > -> This was my first guess, but there's 128MB memory in there 
>> > -> and its a P2-266.
>> > -> It should by all means be fast enough. Besides, if this 
>> > -> would be the case, I
>> > -> would suffer bad performance in Windows 98 too.
>> > -> 
>> > -> > How about trying Samba-2.0.7-ja-2.1 instead of Smaba-2.0.7?
>> > -> 
>> > -> I am yet to try this. I will, but this is not the real 
>> > -> solution to the
>> > -> problem since IMHO the main branch should implement any 
>> > -> patches/fixes for
>> > -> this. But I will see if I can try it out tonight.
>> > -> 
>> > -> > What OS are you using for server? Linux?  Of which version? Did
you
>> > -> > try FreeBSD or NetBSD? Socket layers of *BSD are lot better than
>> > -> > Linux version.
>> > -> 
>> > -> This is also irrelevant, because the problem only surfaces 
>> > -> on Windows 2000
>> > -> clients. However, fyi, I am running Debian 2.2 (Linux) with 
>> > -> kernels 2.2.18
>> > -> and 2.4.0-test12.
>> > -> 
>> > -> 
>> > -> It's just a shame that apparently nobody is looking into 
>> > -> this issue. This
>> > -> isn't just a single case. I have had over 10 emails stating 
>> > -> that they had
>> > -> the exact same performance problem. Sigh...
>> > -> 
>> > -> 
>> > -> 
>> > -> Regards,
>> > -> 
>> > -> infernix
>> > -> 
>> > -> 
>> > 
>> 
>> ---------------------------------------------------------------------
>> Greg Dickie
>> just a guy
>> greg at discreet.com
>> 
> 
> -- 
> 
> --Anders
> 
> Anders C. Thorsen
> PGP Key: http://www.aae.wisc.edu/~anders/anders-pgp.asc
> 
> ----------------------------------------
> Only two things are infinite.
> The universe and human stupidity.
> Although, I am unsure of the former.
> 
> Albert Einstein

---------------------------------------------------------------------
Greg Dickie
just a guy
greg at discreet.com

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