RH 7.1 + kernel 2.4

Josip Loncaric josip at icase.edu
Wed Apr 25 14:36:58 PDT 2001

David van der Spoel wrote:
> On Tue, 17 Apr 2001, Josip Loncaric wrote:
> >FYI: Red Hat 7.1 is out and it includes kernel 2.4:
> Does this make your low-latency patches superfluous yet? I've been using
> the 2.4 kernels for a while now, but communication for small blocks does
> not seem optimal.

RH 7.1 comes with kernel 2.4.2-2 whose TCP stack is substantially
different from the 2.2.x versions, so I cannot answer your question
without some testing.  It will take me a while to test this, since I
have Red Hat 7.1 on only one machine so far.

In the meantime, see if my script 'sfperf' reports performance problems
with small packets (available at http://www.icase.edu/~josip/sfperf with
instructions at http://www.icase.edu/~josip/LinuxTCP-patches.html). 
Since my TCP patches are not applicable to kernel 2.4, sfperf will
report on the variability of test times using your existing network.
This could be helpful in deciding whether these patches might help. 


Dr. Josip Loncaric, Research Fellow               mailto:josip at icase.edu
ICASE, Mail Stop 132C           PGP key at http://www.icase.edu./~josip/
NASA Langley Research Center             mailto:j.loncaric at larc.nasa.gov
Hampton, VA 23681-2199, USA    Tel. +1 757 864-2192  Fax +1 757 864-6134

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