Hi Kostas,
Thanks for getting back to me.
> Are the java processes really use that much memory or is it the buffer
> cache? The kernel will try to cache as many files as possible so high
> memory usage is normal (your ganglia page isn't visible from the outside
> world)
Sorry about the ganglia page, I thought that was now visible. I think you
are correct though, we are seeing high usage of cached memory. Do you
think it would be useful to tune our virtual memory settings as you
mentioned in your previous email (RE: Kernels)?
> What type of disks/controllers do you have? From what i've seen dcache
> generates really bad IO patterns with parallel transfers, have you tried
> running with only one stream and multiple files instead?
I do not know the exact specifications of our disk controllers. I will
find this out for you.
During the FTS tests we were running with 8 files and 0 (?) streams. Can
anyone point me to a webpage with information regarding the difference
between streams and files? With this setup we were seeing ~200Mb/s into
our site.
Thanks,
Greig
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