Problems with network performance.

[Mike Brodbelt]

Hi,

I've recently been investigating network performance with Linux boxes on
your network. I've been using two Linux boxes on my network for a while,
as web/mail/DNS servers, and I'm in the process of moving file storage
over from a Novell Netware 3.12 server to one of the Linux boxes.
However, there is clearly something wrong with the machines, and I'm
currently at a loss to explain what it is. The performace results below
show the sorts of network speed I'm seeing, which is truly awful. Both
boxes are using a Tulip chipset card, and I'm hoping someone here can
shed some light on why I might be getting such bad performace.

Normally, I expect 900 kb/s upwards on a quiet 10 Mb coaxial segment,
and I've no idea what I could possibly have misconfigured to generate
performance as atrocious as I'm seeing. I can provide any more
information that might help on request. If anyone has any ideas, please
let me know - I'm down to swapping out a NIC next weekend otherwise, in
the hope that it may fix the problem....

Here are the performance figures - the ifconfig output and uptimes are
all for machine A, which is the box I'm trying to move file sharing
onto, using Samba. I tend to think that the error rate is way too high,
but I don't know what the cause could be. The network is 10base2, in a
pretty ropy state, so some slow down is perhaps to be expected, but I'd
imagine that I should be seeing at least 600k/s on the FTP. Connection
to the outside world is via a 10Mbps leased line.


Any help would be *much* appreciated,

Mike.

SERVER         CLIENT        XFER RATE    METHOD
======         ======        =========    ======
  A (Linux)      B (Linux)    144 kb/s    FTP (CLI ftp client)
  A (Linux)      B (Linux)    169 kb/s    SMB (smbclient)
  A (Linux)      C (NTWS)      69 kb/s    SMB (NT Explorer)
  D (Netware)    C (NTWS)     692 kb/s    NCP over IPX (NT Explorer)
  E (NTSRV)      C (NTWS)     157 kb/s    SMB (NT Explorer)
  X (Solaris)	 C (NTWS)     443 kb/s    FTP (Netscape)
  X (Solaris)	 A (Linux)    181 kb/s    FTP (CLI ftp client)
  A (Linux)      F (MacOS)     63 kb/s    ASIP (Finder)
  B (Linux)	 C (NTWS)      32 kb/s    SMB (NT Explorer)
  A (Linux)      C (NTWS)      54 kb/s    FTP (CLI ftp client)

eth0      Link encap:Ethernet  HWaddr 00:00:C0:0C:75:E8
          inet addr:194.81.120.81  Bcast:194.81.120.255           
Mask:255.255.255.0
          EtherTalk Phase 2 addr:1/242
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:18457653 errors:1717 dropped:0 overruns:0
          TX packets:15145268 errors:79182 dropped:0 overruns:0
          Interrupt:11 Base address:0xb800 

5:04pm  up 38 days,  3:34,  3 users,  load average: 0.00, 0.00, 0.00

eth0      Link encap:Ethernet  HWaddr 00:00:C0:0C:75:E8
          inet addr:194.81.120.81  Bcast:194.81.120.255 
          Mask:255.255.255.0
          EtherTalk Phase 2 addr:1/242
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:18831732 errors:1777 dropped:0 overruns:0
          TX packets:15463638 errors:81207 dropped:0 overruns:0
          Interrupt:11 Base address:0xb800 

12:33pm  up 38 days, 23:03,  5 users,  load average: 0.02, 0.05, 0.00

Errors shot up to 81K during mornings testing.

Machine specifications:-

A - Intel PII-350, 256Mb RAM, 12GB SCSI disk, RAID 5, SMC EtherEZ NIC,
with DEC 21041 tulip chipset (tulip.c v0.89H). Linux 2.0.36, RedHat 5.1,
Samba 2.0.3

B - Intel P-166, 32Mb RAM, 2GB SCSI disk, DEC DS21041 Tulip (tulip.c
v0.79). Linux 2.0.32, RedHat 4.1, Samba 1.9.17

C - Intel PII-233, 128Mb RAM, 3GB IDE disk, DEC 21041 based NIC. Windows
NT WS 4.0 (sp4).

D - Intel P-100, 64Mb RAM, 4GB SCSI disk, Novell NE2000 (ISA). Novell
Netware 3.12

E - Intel PPro-200, 128Mb RAM, 4GB SCSI DISK, RAID 1 (SW), DEC 21041
based NIC. Windows NT SRV 4.0 (sp3).

F - Macintosh G3 - PowerPC 266, 64Mb RAM, 3GB IDE disk, Kingston NIC.
MacOS 8.1

X - Arbitrary external host (src.doc.ic.ac.uk)