I have a lab of machines with Intel eepro 100+ adaptors all running etherboot/netboot and a beowulf with Intel/DEC 21143-based adaptors also running etherboot/netboot. In both cases the machines are loading a 5.4MB boot image (compressed kernel + compressed initial RAM disk). In the case of the eepro 100 machines, even on a relatively busy network, I can get the image TFTP'd in about 3.6 seconds (= 1.5MBytes/sec) which isn't too bad - clearly faster than 10Mbps but, not surprisingly, not using anywhere near all of the 100Mbps available. In the case of the 21143 based machines, even on a completely quiet network, ntulip is taking over 42 seconds to load the same size file. I have checked with tcpdump in both situations. In the case of the eepro100's, the 516byte TFTP frames are sent out about once every 350usec (there are about 10,600 such frames). In the case of the ntulip 21143's, the frames are sent out every 3900usec. It looks suspiciously as though the 21143 is running about 1/10 as fast, and yet, even at 10Mbps, a 516 byte frame should only take about 440usec, plus, the managed switch assures me that it is connected to the 21143 card at 100Mbps Full Duplex during the 42 second download. Once Linux is up and running, I am getting a little over 8MByte/sec NFS from the 21143 card, which is about as good as you can expect from NFS across a 100Mbps full duplex link, so that indicates that the card itself is not the problem. Anyone got any idea as to why the eepro100 driver is so much faster at the TFTP than the ntulip driver? I have tried playing with UADJUST and other timing related variables, with no positive effect, and usually the negative effect of causing the TFTP to hang up. Any help or suggestions would be much appreciated. Cheers, Bob Edwards. =========================================================================== This Mail was sent to netboot mailing list by: Bob Edwards <Robert.Edwards@anu.edu.au> To get help about this list, send a mail with 'help' as the only string in it's body to email@example.com. If you have problems with this list, send a mail to firstname.lastname@example.org.
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