--- On Thu, 4/7/11, Chuck Lever <chuck.lever@xxxxxxxxxx> wrote: > On Apr 7, 2011, at 10:34 AM, Andrew Klaassen wrote: > > > --- On Thu, 4/7/11, Chuck Lever <chuck.lever@xxxxxxxxxx> > wrote: > >> Have you created enough nfsd threads on your Linux NFS > >> servers? > > > > That was one of the things I varied as part of my > > testing; almost every power of 2 from 8 threads up to 1024 > > threads. It actually made things slightly worse, not > > better, but I can certainly give it a try again. > > Is the server an SMP system? Yes. > Do you see high CPU load during times of slow performance? I've found two cases when throughput is high and "ls -l" is slow: - disk-bound, when I'm (purposely) pumping through more data than can be held in the cache. In this case, CPU idle time generally remains between 30-60%. - fully-cached read-only, when... well, it looks like I'll have to get back to you on this one, since ext4lazyinit has to finish its thing before I can reproduce this case. I do notice that ksoftirqd is eating up 100% of a core when I'm loading the server heavily. I assume that's because I'm not using jumbo frames and the ethernet cards are spitting out interrupts as fast as they're able. Unfortunately, upgrading the hardware - either disks or CPU - is not an option. This is why I was hoping there was some way to send readdirplus/getattr/lookup calls to the front of the queue on the server side even when the hardware has reached its limits. Andrew -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
