From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 25 Aug 2004 00:20:26 +0100 (BST) From: Hugh Dickins Subject: Re: [Bug 3268] New: Lowmemory exhaustion problem with v2.6.8.1-mm4 16gb In-Reply-To: <20040824144312.09b4af42.akpm@osdl.org> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: kmannth@us.ibm.com, linux-mm@kvack.org List-ID: On Tue, 24 Aug 2004, Andrew Morton wrote: > bugme-daemon@osdl.org wrote: > > > > http://bugme.osdl.org/show_bug.cgi?id=3268 > > > > Summary: Lowmemory exhaustion problem with v2.6.8.1-mm4 16gb > > Problem Description: I run out of lowmemory very easily using /dev/shm/ > > I have 64g and Numa/Discontig enabled in my kernel. > > > > Steps to reproduce: Fill up 1/2 or more of /dev/shm (on my system it is about > > 1/3-1/2 of my total system memory) with lots of kernel builds. Observe system > > breakdown. (If you want the script I will email it to you). I have seen this > > with both 32 gigs and 16 gigs... > > I assume this is because we're using up all of lowmem with filesystem metadata. > > Hugh? Probably, though it's not something anyone reported before. Filesystem metadata being, not tmpfs's indirect blocks (which use highmem), but the plenitude of inodes and dentries: which would get pruned if it were a disk-based filesystem, but cannot because this one is all in memory. I've not done the arithmetic... tomorrow. I'll try to reproduce something similar (I don't have 16GB and I don't have NUMA, though latter probably not relevant) tomorrow, and fix (decide default nr_inodes by lowmem). Keith, please do mail me your script (in case there's something special in there e.g. will make a difference if your sources are linked or not), and also your /proc/slabinfo near OOMing, if that's convenient. Thanks, Hugh -- 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: aart@kvack.org