----- Original Message ---- > From: "Witham, Timothy D" <[EMAIL PROTECTED]> > To: "Escobio, Roger " <[EMAIL PROTECTED]>; > "ganglia-general@lists.sourceforge.net" > <ganglia-general@lists.sourceforge.net> > Sent: Tuesday, September 9, 2008 9:42:34 PM > Subject: Re: [Ganglia-general] Anyone experience petabyte peaks in network > metric in ganglia 3.x.y ? > > >I am testing ganglia in a cluster of linux but we are getting this > >confusing peaks in the bytes/s and in the packets/s (image attached) > > I have been able to minimize this significantly by using code from svn trunk > and > building with > > make CPPFLAGS=-DREMOVE_BOGUS_SPIKES > > IMHO, that should be the default. > Hi Tim,
the problem is that with NICs faster than 1000 Mbit, the naturally occuring wrap-arounds will come too frequently (especially for the byte counters) and will trigger the remove mechanism and really mess up the data. The better solution would be to bring the networking counters in the Linux kernel to 64-bit (they are 32-bit right now). Then we would not have to care about natural wrap-around for a few years. I once proposed this change, but it was not greeted with much enthusiasm :-( Therefore I #ifdef-ed my check. Especailly as the effect seems to be really a very NIC specific bug. Escobio -> what NICs are in the systems in question (all the same?). As I undertand, you are using some 2.6.9 kernel? Cheers Martin ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Ganglia-general mailing list Ganglia-general@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/ganglia-general
