From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin J. Bligh" Date: Tue, 14 Dec 2004 20:08:44 +0000 Subject: Re: [PATCH 0/3] NUMA boot hash allocation interleaving Message-Id: <19030000.1103054924@flay> List-Id: References: <9250000.1103050790@flay> <20041214191348.GA27225@wotan.suse.de> In-Reply-To: <20041214191348.GA27225@wotan.suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Andi Kleen Cc: Brent Casavant , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-ia64@vger.kernel.org --On Tuesday, December 14, 2004 20:13:48 +0100 Andi Kleen wrote: > On Tue, Dec 14, 2004 at 10:59:50AM -0800, Martin J. Bligh wrote: >> > NUMA systems running current Linux kernels suffer from substantial >> > inequities in the amount of memory allocated from each NUMA node >> > during boot. In particular, several large hashes are allocated >> > using alloc_bootmem, and as such are allocated contiguously from >> > a single node each. >> >> Yup, makes a lot of sense to me to stripe these, for the caches that > > I originally was a bit worried about the TLB usage, but it doesn't > seem to be a too big issue (hopefully the benchmarks weren't too > micro though) Well, as long as we stripe on large page boundaries, it should be fine, I'd think. On PPC64, it'll screw the SLB, but ... tough ;-) We can either turn it off, or only do it on things larger than the segment size, and just round-robin the rest, or allocate from node with most free. >> didn't Manfred or someone (Andi?) do this before? Or did that never >> get accepted? I know we talked about it a while back. > > I talked about it, but never implemented it. I am not aware of any > other implementation of this before Brent's. Cool, must have been my imagination ;-) M.