Displaying 1 result from an estimated 1 matches for "lustre_bc_overhead".
2013 Aug 22
13
Lustre buffer cache causes large system overhead.
...akes more than
200 secs. After running "echo 3 > /proc/sys/vm/drop_caches" the system
performance goes back to normal with a run time at 150 secs.
I''ve created an infographic from our ganglia graphs for the above scenario.
https://dl.dropboxusercontent.com/u/23468442/misc/lustre_bc_overhead.png
Attached is an excerpt from perf top indicating that the kernel routine taking
the most time is _spin_lock_irqsave if that means anything to anyone.
Things tested:
It does not seem to matter if we mount lustre over infiniband or ethernet.
Filling the buffer cache with files from an NFS fi...