On Sat, 2 Jun 2007, David Mathog wrote:
I can't quite wrap my head around a recent nettee result, perhaps one of the network gurus here can explain it.
IMHO, it's not a network issue, as is shown by your G results.
sync; accudate; dd if=/dev/zero bs=512 count=1000000 of=test.dat;
All your tests use bs=512 - why ? This makes unnecessary trips to kernel code and back which result in an increased number of context switches and significant slowdown. My guess is that this (high number of context switches) plus a high interrupt rate (disk and network simultaneously) is the reason for your results.
Old: Athlon MP 2200+, Tyan S2466MPX mobo, 2.6.19.3 kernel, 512Mb RAM
I used to have the exact same hardware as cluster nodes (but with dual CPU, whether you also have duals is not clear from your post) and tried to convert 2 of them to small file-servers - same problem of disk + network simultaneous activity. After benchmarking, I gave up - this was almost 2 years ago and I don't have the exact numbers anymore, but a single PIV 3GHz on a consumer-grade mainboard was able to provide significantly better performance for the same task.
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