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Re: Pipeline Production Problems
Rob,
I think you missed a post. Tom has two switches daiy chained.
When any of the PCs on switch one need to send data to any of the
PCs on switch two the data must go over the uplink cable.
There is a 100Mbps bottle neck between the two switches.
Looks like he has the Windows camera controlers all on one
switch and the data pipeine boxes on a second switch. He needs
to buy one big switch and pull more wire or just put up with it.
--- Robert Creager <Robert_Creager@LogicalChaos.org> wrote:
> When grilled further on (Mon, 13 Oct 2003 16:01:08 -0500),
> "Thomas Droege" <tdroege2@earthlink.net> confessed:
>
> >
> > >From the looks of things, the transmission speed goes down as I
> start each
> > transfer process going. I could add some extra cables so that the
> possible
> > routes had parallel cables if the system is smart enough to make
> use of
> > them.
>
> I'm wondering if the transmission speed is either CPU or 'hub'
> related.
>
> I just did a few tests. I created a 2Gbyte file from /dev/urandom,
> and did a
> scp between my server with a 1000Mbit pipe going into a 100Mbit
> switch through
> three other 100Mbit switches to an PII 400Mhz 128Mbyte ram in 7:40
> minutes
> (4.4Mbytes/sec). Then to my AMD K62 500Mhz 664Mbyte ram through one
> switch in
> 19:58 minutes (1.7Mbytes/sec). The AMD was definitely CPU bound. I
> didn't pay
> attention to the P2 CPU usage. The server is a 2xAMD 2600+ with
> 2Gbytes memory.
>
> I then went to NFS, and managed the 2Gbyte copy in 3:25 minutes to
> the PII, or
> just shy of 10Mbytes/second, which is pretty darn close to the
> theoretical
> maximum of a 100Mbit connection. The AMD clicked along quite nicely
> in 11:54
> minutes (2.9Mbytes/second), with out being CPU bound.
>
> As a last try, I did both at the same time. The PII completed in 4
> minutes for
> 8.5Mbytes/second, and I'm going to bed before the AMD will finish. I
> am doing
> the NFS mount from an IDE disk, not my SCSI disk, which might be why
> it took an
> extra 35 seconds.
>
> What's all this say? My AMD has a crappy network card and Tom
> shouldn't be
> seeing significant slowdowns unless he is running hubs, or has crappy
> network
> cards also... I suspect his PC's are all faster than my PII and AMD,
> and should
> be able to maintain full bandwidth.
>
> Cheers,
> Rob
>
> --
> 22:05:15 up 73 days, 14:32, 5 users, load average: 2.50, 2.53,
> 2.55
>
> ATTACHMENT part 2 application/pgp-signature
=====
Chris Albertson
Home: 310-376-1029 chrisalbertson90278@yahoo.com
Cell: 310-990-7550
Office: 310-336-5189 Christopher.J.Albertson@aero.org
KG6OMK
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