On the larger, cellular Itanium systems with multiple motherboards (rx6600 to Superdome) Oracle has done a lot of tuning with the HP-UX kernel calls to optimize for NUMA issues. Will be interesting to see what they bring to Linux.
On Tue, Jul 17, 2012 at 7:52 PM, Greg Smith <greg@2ndquadrant.com> wrote: > Newer Linux systems with lots of cores have a problem I've been running into > a lot more lately I wanted to share initial notes on. My "newer" means > running the 2.6.32 kernel or later, since I mostly track "enterprise" Linux > distributions like RHEL6 and Debian Squeeze. The issue is around Linux's > zone_reclaim feature. When it pops up, turning that feature off help a lot. > Details on what I understand of the problem are below, and as always things > may have changed already in even newer kernels.
Thanks for the link, I'll read up on it. I do have access to large (24 to 40 core) NUMA machines so I might try some benchmarking on them to see how they work.