From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: Date: Mon, 3 Sep 2007 16:41:30 -0500 From: "Eric Van Hensbergen" To: "Fans of the OS Plan 9 from Bell Labs" <9fans@cse.psu.edu> Subject: Re: [9fans] plan 9 overcommits memory? In-Reply-To: <13426df10709031419n16ae32f2i109d1be5948d074b@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <2c68bbb34242a932e4b3e9be554c6f18@quanstro.net> <13426df10709031419n16ae32f2i109d1be5948d074b@mail.gmail.com> Topicbox-Message-UUID: b6a4a290-ead2-11e9-9d60-3106f5b1d025 I was thinking that this was probably what we wanted to do for HPC.... also, having the option of turning off zero-filling pages.... -eric On 9/3/07, ron minnich wrote: > One option for Erik: try changing the segment allocator so that it > faults in all segment pages on creation. Would this do what you want? > I will try this if I get time later today. Assuming it is as simple as > my simple-minded description makes it sound. > > If it would, maybe a simple > echo faultall > /proc/pid/ctl > would be useful > > would be interesting: iterate over all segments, and make sure each > has a real page for all pages in all segments. > > I can see the need for not overcommitting, and also for actually > creating and filling out the pages on malloc or other allocation. > Indeed, lack of OS thrashing due to paging is one feature cited by > proponents of this: > http://www.cs.sandia.gov/~smkelly/SAND2006-2561C-CUG2006-CatamountDualCore.pdf > > ron >