From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from max.phys.uu.nl (max.phys.uu.nl [131.211.32.73]) by kvack.org (8.8.7/8.8.7) with ESMTP id EAA06246 for ; Fri, 27 Nov 1998 04:24:55 -0500 Date: Fri, 27 Nov 1998 06:27:04 +0100 (CET) From: Rik van Riel Reply-To: Rik van Riel Subject: borrow percentages & new VM scheme Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Linus Torvalds Cc: Linux MM List-ID: Hi, I've found that the rediculous amount of swapping associated with 2.1.130-pre3 goes away if you reduce the borrow percentages for both buffer and page cache to 10 percent... We probably want 15% for the borrow percentage on small (<32M) boxes, but nothing more either. Lowering the borrow percentage gives kswapd the 'need' to prune the cache once in a while, even when it is still easy to unmap something in swap_out(). Because kswapd usually only switches when there is a failure for either swap_out() or shrink_mmap() it can continue with swap_out() (since there still is not enough memory free) doing 1000+ swapouts a second for a 7 second period (on my box) which is just a bit too much. We need some sort of mechanism to make kswapd switch tactics more often, or else system stability and performance may suffer. regards, Rik -- now completely used to dvorak kbd layout... +-------------------------------------------------------------------+ | Linux memory management tour guide. H.H.vanRiel@phys.uu.nl | | Scouting Vries cubscout leader. http://www.phys.uu.nl/~riel/ | +-------------------------------------------------------------------+ -- This is a majordomo managed list. To unsubscribe, send a message with the body 'unsubscribe linux-mm me@address' to: majordomo@kvack.org