From: dan.j.williams(a)gmail.com [mailto:email@example.com] On
Behalf Of Dan Williams
Sent: Saturday, May 16, 2015 10:22 PM
To: Elliott, Robert (Server Storage)
Cc: linux-nvdimm(a)lists.01.org; Neil Brown; Greg KH; Dave Chinner; linux-
kernel(a)vger.kernel.org; Andy Lutomirski; Jens Axboe; H. Peter Anvin;
Christoph Hellwig; Ingo Molnar
Subject: Re: [Linux-nvdimm] [PATCH v2 19/20] nd_btt: atomic sector
On Sat, May 16, 2015 at 6:19 PM, Elliott, Robert (Server Storage)
2 items to check:
1/ make sure you have a your btt sector size set to 4k which cuts down
the overhead by a factor of 8.
2/ boot with nr_cpus=256 or lower.
Ross noticed that CONFIG_NR_CPUS is set quite high on distro kernels
which revealed that we should have been using nr_cpu_ids and percpu
variables for nd_region_acquire_lane() from the outset. This fix is
coming in v3.
My system does have CONFIG_NR_CPUS=8192. I'll try the items you