From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 3F4FF6B006A for ; Thu, 8 Jul 2010 00:59:17 -0400 (EDT) Received: by iwn2 with SMTP id 2so600116iwn.14 for ; Wed, 07 Jul 2010 21:59:15 -0700 (PDT) MIME-Version: 1.0 Date: Thu, 8 Jul 2010 10:29:15 +0530 Message-ID: Subject: Ramzswap :swap-device write failure under low memory From: Uma shankar Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org To: linux-mm@kvack.org List-ID: Hi, When using ramzswap, the internal allocator (xvMalloc) will try to grow the pool, when the compressed block will not fit in any of the existing free chunk. This memory allocation can fail under low memory. This will be informed to the kernel as a "device write" failure. The page which was being written will not be reclaimed, but the kernel will continue to try swap out of other pages ( as kernel thinks that swap has free space. ) Wont this lead to the reclaim code ( kswapd or the direct reclaim path ) hogging the processor for some time before OOM is finally announced ? Has any one analysed this scenario ? thanks shankar -- 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