From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sap-ag.de ([194.39.131.3]) by smtpde02.sap-ag.de (out) with ESMTP id TAA29354 for ; Sun, 19 Nov 2000 19:08:27 +0100 (MEZ) Received: from linux.local.wdf.sap-ag.de (ct4012.wdf.sap-ag.de [147.204.29.12]) by sap-ag.de (8.8.8/8.8.8) with SMTP id TAA28508 for ; Sun, 19 Nov 2000 19:13:20 +0100 (MET) Resent-Message-Id: <200011191813.TAA28508@sap-ag.de> Resent-To: linux-mm@kvack.org Subject: Re: Hung kswapd (2.4.0-t11p5) References: <3A146EDA.36D1F9C4@redhat.com> From: Christoph Rohland In-Reply-To: Bob Matthews's message of "Thu, 16 Nov 2000 18:33:46 -0500" Date: 19 Nov 2000 15:34:42 +0100 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linux-mm@kvack.org Return-Path: To: Bob Matthews Cc: riel@nl.linux.org, johnsonm@redhat.com List-ID: Hi Bob and Rik, Bob Matthews writes: > kswapd itself appears to be stuck here: > > (gdb) list *0xc01394c2 > 0xc01394c2 is in create_buffers (buffer.c:1240). > 1235 > 1236 /* > 1237 * Set our state for sleeping, then check again for buffer heads. > 1238 * This ensures we won't miss a wake_up from an interrupt. > 1239 */ > 1240 wait_event(buffer_wait, nr_unused_buffer_heads >= > MAX_BUF_PER_PAGE); > 1241 goto try_again; > 1242 } > 1243 > 1244 static int create_page_buffers(int rw, struct page *page, kdev_t > dev, int b[], int size) That's apparently exactly the same place shm swapping gets stuck. Apparently we run out of buffer heads on highmem machines (I actually believe that we can trigger the same on lowmem machines also, only under much higher load wrt the machine size, but that's only a guess) Greetings Christoph -- 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/