From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <432F7DD5.6050204@ccoss.com.cn> Date: Tue, 20 Sep 2005 11:11:17 +0800 From: liyu MIME-Version: 1.0 Subject: [Question] How to understand Clock-Pro algorithm? Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: LKML , Linux-MM List-ID: Hi, every in LKML/linux-mm: I have been read CLOCK-Pro paper since last week, and am going to write one python demo. After just read , I think I can understand it, however once I begin implement it, I found there are many point that not clear. First, two important parameters Mc, Mh, In that paper, it assume total memory size is M. (in number of page) There is a formula: M = Mc+Mh. Mc, number of cold pages in memory, Mh, number of hot pages in memory. So, in clock list, we can keep track 2M page metadatas at most, we may include M non-resident pages. In '4.3 operationes on searching vicim pages' , the authors said "we keep track of the number of non-resident cold pages, Once the number exceeds m the memory size in number of pages. we terminted the test period of the cold page pointed to by HAND-test." My question is out:As this paper words, the number of cold page is total of resident cold pages and non-resident pages. It's the seem number of non-resident cold pages can not beyond M at all! I also have more questions on CLOCK-Pro. but this question is most doublt for me. Any clear word is welcome. thank in advanced. I suppose experience is more important than theory in page-replacement field, is it right? liyu -- 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