From mboxrd@z Thu Jan 1 00:00:00 1970 Message-Id: <200508042258.j74Mwsg18638@unix-os.sc.intel.com> From: "Chen, Kenneth W" Subject: RE: Getting rid of SHMMAX/SHMALL ? Date: Thu, 4 Aug 2005 15:58:52 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit In-Reply-To: <20050804225413.GH8266@wotan.suse.de> Sender: owner-linux-mm@kvack.org Return-Path: To: 'Andi Kleen' Cc: Hugh Dickins , linux-kernel@vger.kernel.org, Anton Blanchard , cr@sap.com, linux-mm@kvack.org List-ID: Andi Kleen wrote on Thursday, August 04, 2005 3:54 PM > > This might be too low on large system. We usually stress shm pretty hard > > for db application and usually use more than 87% of total memory in just > > one shm segment. So I prefer either no limit or a tunable. > > With large system you mean >32GB right? Yes, between 32 GB - 128 GB. On larger numa box in the 256 GB and upward, we have to break shm segment into one per-numa-node and then the limit should be OK. I was concerned with SMP box with large memory. > I think on a large systems some tuning is reasonable because they likely > have trained admins. I'm more worried on reasonable defaults for the > class of systems with 0-4GB Sounds reasonable to me. - Ken -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org