Re: Linux 1.3.59 Netperf with large packets

Alan Cox (alan@lxorguk.ukuu.org.uk)
Sun, 25 Feb 1996 13:04:59 +0000 (GMT)


> I'm running Linux 1.3.59 and I see funny behavior with
> large packets. We've got a Myrinet card in the
> machine that has an MTU of 8432 bytes. Perhaps
> Linux hasn't ever needed to deal with messages larger
> than 4k?

The atomic memory allocator doesnt guarantee single
atomic allocations of one page. So if you dont have
a fair bit of free memory you won't get useful results.

Various people have talked about fixing this, but it
makes a significant dent in performance to try and
address it.

Alan