On Thu, 2005-03-31 at 16:50 +0200, Ingo Molnar wrote: > * Ingo Molnar <[EMAIL PROTECTED]> wrote: > > > > So the overhead you are currently seeing should just be that of > > > iterating through the list, locking said requests and adding them to > > > our private list. > > > > ah - cool! This was a 100 MB writeout so having 3.7 msecs to process > > 20K+ pages is not unreasonable. To break the latency, can i just do a > > simple lock-break, via the patch below? > > with this patch the worst-case latency during NFS writeout is down to 40 > usecs (!). > > Lee: i've uploaded the -42-05 release with this patch included - could > you test it on your (no doubt more complex than mine) NFS setup?
This fixes all the NFS related latency problems I was seeing. Now the longest latency from an NFS kernel compile with "make -j64" is 391 usecs in get_swap_page. Lee - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/