From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 22 Jun 2000 13:38:39 -0300 (BRST) From: Rik van Riel Subject: Re: [RFC] RSS guarantees and limits In-Reply-To: <85256906.0059E21B.00@D51MTA03.pok.ibm.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: frankeh@us.ibm.com Cc: linux-mm@kvack.org List-ID: On Thu, 22 Jun 2000 frankeh@us.ibm.com wrote: > Now I understand this much better. The RSS guarantee is a > function of the refault-rate . This in principle > implements a decay of the limit based on usage.... I like that > approach. My previous anti-hog code (it even seemed to work) was to "push" big processes harder than small processes. If, for example, process A is N times bigger than process B, every page in process A would get sqrt(N) times the memory pressure a page in process B would get. This promotes fairness between memory hogs. This code will adjust the guarantee and the limit to the type of memory usage, so a process which streams over a huge amount of data just once will be restricted to maybe a few times its window size so it'll be unable to push other processes out of memory by simply accessing all the data quickly (but just once). For a fair VM we probably want a combination of this new idea *and* some fairness measures. Preferably in such a way that we don't interfere too much with the strategy of global page replacement... > Is there a hardstop RSS limit below you will not evict pages > from a process (e.g. mem_size / MAX_PROCESSES ?) to give some > interactivity for processes that haven't executed for a while, > or you just let it go down based on the refault-rate... There is none, but maybe we should have the RSS guarantee just go down slower and slower depending on the size of the process? regards, Rik -- The Internet is not a network of computers. It is a network of people. That is its real strength. Wanna talk about the kernel? irc.openprojects.net / #kernelnewbies http://www.conectiva.com/ http://www.surriel.com/ -- 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.eu.org/Linux-MM/