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<font size=3>Brendan,<br><br>
If you are doing this via nfs, you should be sure that mounts are done
using the tcp parameter in /etc/fstab. Otherwise you may get udp,
and I have seen problems with that as recently as Fedora 8 this
morning!<br><br>
<br>
Mike<br><br>
At 08:03 PM 12/17/2007, Brendan Moloney wrote:<br>
<blockquote type=cite class=cite cite="">I have a cluster of 8 Linux
machines connected with gigabit ethernet (full duplex) to a HP Procurve
2848 switch. I am using the machines to do interactive
distributed rendering. I have noticed that the final gather stage
(where the intermediate images from the render nodes are sent back to the
viewing node) has "hiccups" in the performance. These
hiccups occur with as few as two render nodes, and become more common as
I add more render nodes. With a 512x512 image the final gather
usually takes a few milliseconds for each frame, but when the hiccups
occur it is more like 200+ milliseconds. <br><br>
Since it is a full duplex switched network, there should not be any
collisions happening. Since the image is less than 1 MB total, I
don't think I am saturating the switch. I have checked the contents
of /sbin/ifconfig and there are zero erroneous packets being
reported. At this point I am really at a loss as to what is causing
this. Any input on things to check would be greatly appreciated.
<br><br>
Thanks,<br>
Brendan<br>
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