Thanks again Denice. As a courtesy, I'll be sure to post back should the xfs group assist in resolving the issue.
Thank you On Wed, Dec 7, 2011 at 5:18 PM, Denice <[email protected]> wrote: > On Wed, 7 Dec 2011, Ryan C. England wrote: > > I have included the current value of vm.min_free_kbytes below. >> [root@localhost ~]# cat /proc/sys/vm/min_free_kbytes >> 90112 >> > > We typically (at SL 5 though) double the anaconda-configured value. > It is easy enough to change and test dynamically .. > > > On Wed, Dec 7, 2011 at 1:58 PM, Ryan C. England < >> [email protected]> >> wrote: >> Denice, >> First and foremost, thank you for the reply. I have included the I/O >> stack for your convenience. >> >> nfs, xfs, lvm, megaraid_sas >> >> I could get rid of lvm layer, but the others are required. We're >> currently using this as our NAS. When the array was created, ext4 was >> not yet widely adopted so we chose to go with xfs. >> >> What value should I set for vm.min_free_kbytes? In further >> researching the issue, I have discovered that 2.6.35 includes "xfs: >> skip writeback from reclaim context." Should I entertain the idea of >> using a newer version of the kernel? >> > > probably only if you are comfortable doing it, and have some kind of a > test system. > > I would join the XFS mailing list, and ask some experts. > > http://oss.sgi.com/mailman/**listinfo/xfs<http://oss.sgi.com/mailman/listinfo/xfs> > > At SL6 I think you can enable some debugging by mounting debugfs > and get some stack traces (some one is probably going to ask for them). > This seems to work for me, but your mileage may very: > > # ls /sys/kernel/debug/ > > # mount -t debugfs nodev /sys/kernel/debug > # ls /sys/kernel/debug/ > bdi dynamic_debug kprobes sched_features x86 > boot_params extfrag kvm tracing xen > dri hid mce usb > > # cat /sys/kernel/debug/tracing/**stack_trace > Depth Size Location (-1 entries) > ----- ---- -------- > # > # Stack tracer disabled > ...... > > # echo 1 > /proc/sys/kernel/stack_tracer_**enabled > # cat /sys/kernel/debug/tracing/**stack_trace > Depth Size Location (42 entries) > ----- ---- -------- > 0) 3200 48 walk_tg_tree+0x6a/0xb0 > ........ > > > cheers, etc. > > -- > deatrich @ triumf.ca, Science/Atlas PH: +1 604-222-7665 > <*> This moment's fortune cookie: > To love is good, love being difficult. -- Ryan C. England Corvid Technologies <http://www.corvidtec.com/> office: 704-799-6944 x158 cell: 980-521-2297
