On Thu, Jul 25, 2013 at 04:38:00PM -0700, Greg Kroah-Hartman wrote: > On Thu, Jul 25, 2013 at 04:11:20PM -0500, Seth Jennings wrote: > > From: Nathan Fontenot <nf...@linux.vnet.ibm.com> > > > > Large memory systems (1TB or more) experience boot delays on the order > > of minutes due to the initializing the memory configuration part of > > sysfs at /sys/devices/system/memory/. > > > > ppc64 has a memory block size of 256M and (I think) x86 is 128M. With 1TB > > of RAM and a 256M block size, that's 4k memory blocks with 20 sysfs > > entries per block that's around 80k items that need be created at boot > > time in sysfs. Some systems go up to 16TB where the issue is > > even more severe. > > > > This patch is a prototype for a new sysfs memory layout where the > > entries are created on demand by writing memory block numbers into a > > "show" and "hide" files to create and destroy the memory block > > configuration attributes in sysfs. This would decouple the number of > > sysfs entries created at boot time from the memory size, resulting in a > > sysfs initialization time that doesn't increase and memory size > > increase. > > > > Signed-off-by: Seth Jennings <sjenn...@linux.vnet.ibm.com> > > Signed-off-by: Nathan Fontenot <nf...@linux.vnet.ibm.com> > > How does this tie into the patches Nathan sent yesterday for memory > hotplug stuff that I thought modified the same part of the kernel?
So this patch introduces the new layout in a new file drives/base/memfs.c (which, in light of your last comment should probably be something more like largememory.c). It doesn't clash with Nathan's, but it doesn't contain the new is_memblock_[removable|offline] functions or the new "release" attribute. But that can be added easily. Seth -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
