From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from flinx.npwt.net (eric@flinx.npwt.net [208.236.161.237]) by kvack.org (8.8.7/8.8.7) with ESMTP id BAA07906 for ; Fri, 12 Jun 1998 01:06:11 -0400 Subject: Q: I can get kswapd to run but not swap anything... From: ebiederm+eric@npwt.net (Eric W. Biederman) Date: 12 Jun 1998 00:18:53 -0500 Message-ID: Sender: owner-linux-mm@kvack.org To: linux-mm@kvack.org List-ID: With my shmfs code on linux-2.1.101 after untaring two kernel source trees, on my 32M machine, kswapd eats about 20% of the cpu time according to swap but nearly nothing is written out. Currently I use shrink_mmap to write out pages. If a page has a use count of 1 and is dirty it gets written to swap and the dirty bit removed instead of being removed from the page cache, and shrink_mmap returns 1. With 2.0.32 using exactly the same approach everything works fine, and while there is a slight performance hit for lots of writes, the system is always quite usable. Does anyone have a clue why my machine becomes nearly unusable with 2.1.101 in this fashion? I am asking this here because a) my changes are quite small and have worked reasonably well on other kernels, and b) something else may be able to trigger the same condition. If it helps at all I am pretty certain that running lots of file writes through my filesystem is a pretty good way of fragmenting memory. Eric