From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: To: 9fans@cse.psu.edu Subject: Re: [9fans] plan 9 overcommits memory? Date: Mon, 3 Sep 2007 14:13:27 -0400 From: geoff@plan9.bell-labs.com In-Reply-To: <20070903053514.GB24296@bio.cse.psu.edu> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Topicbox-Message-UUID: b62d4358-ead2-11e9-9d60-3106f5b1d025 One might allocate at least 3.2GB of swap for a 4GB machine, but many of our machines run with no swap, and we're probably not alone. And 200 processes are not a lot. Would you really have over 32GB of swap allocated for a 4GB machine with 2,000 processes? Programs can use a surprising amount of stack space. A recent notable example is venti/copy when copying from a nightly fossil dump score. I think we want to be generous about maximum stack sizes. I don't think that estimates of VM usage would be an improvement. If we can't get it exactly right, there will always be complaints.