[OpenAFS] Re: Speed of AFS

[Mike Fedyk]

Lars Schimmer wrote:

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> Mitch Collinsworth schrieb:
>
> | The duplex mismatch issue is a huge speed killer, and none of the 
> things
> | you mentioned are relevent to verifying it.  If you have managed 
> switches
> | you need to make sure that either each switch port's duplex setting
> | matches that of the machine or switch plugged into it.  In other words
> | both ends of every cable must be configured the same.
> |
> | auto <--> auto
> | full <--> full
> | half <--> half
> |
> | Actually half <--> auto will work ok but the big thing many folks 
> miss is
> | that full <--> auto will NOT work correctly.  If you do this the 
> auto end
> | will configure itself to half and your throughput speed will be very
> | slow on that connection.
> |
> | If you have unmanaged switches, every port is by default auto and you
> | must make sure everything connected to it is set to auto.
> |
> | If you have any hubs, every port is by default half so you can set the
> | devices it connects to to either auto or half but not full.
> |
> | Yes it's a bit confusing at first but it makes a huge difference.
>
> Thx for your note, but the network here is built 4 years agon complete 
> new and
> the manageable nortel switche are new, to. Every PC should have 
> FullDuplex
> 100Mbit in our net, if not, the hardware is not OK.

That does not account for negotiation conflicts between the network 
components.  I have seen this with a Cisco 3500XL and some ethernet 
cards (mostly onboard ethernet chips though).

> But to be safe, I managed to control some servers/clients, all FD, but 
> our main
> cell server had a 3com card set to 10MBit *WTF*, changed 10 min. ago. 
> Now the
> speed is under 3 MB, again. But with a quick glance on the server, the 
> PII has
> the HD in pio mode, so the fileserver is at 95% load for the PII, 
> thats far to
> much. I have to change the PC to a faster, stronger one :-)

Just plug in a PCI ide card, and you should be set.  Your old system 
should be able to perform well after that.