From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) (using TLSv1 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id DB09B1A0034 for ; Wed, 9 Mar 2016 00:25:46 +1100 (AEDT) Subject: Re: [PATCH 1/2] mm: meminit: initialise more memory for inode/dentry hash tables in early boot To: Li Zhang , akpm@linux-foundation.org, mgorman@techsingularity.net, mpe@ellerman.id.au, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com References: <1457409354-10867-1-git-send-email-zhlcindy@gmail.com> <1457409354-10867-2-git-send-email-zhlcindy@gmail.com> Cc: linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Li Zhang From: Vlastimil Babka Message-ID: <56DED2D4.4060805@suse.cz> Date: Tue, 8 Mar 2016 14:25:40 +0100 MIME-Version: 1.0 In-Reply-To: <1457409354-10867-2-git-send-email-zhlcindy@gmail.com> Content-Type: text/plain; charset=utf-8 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 03/08/2016 04:55 AM, Li Zhang wrote: > From: Li Zhang > > This patch is based on Mel Gorman's old patch in the mailing list, > https://lkml.org/lkml/2015/5/5/280 which is discussed but it is > fixed with a completion to wait for all memory initialised in > page_alloc_init_late(). It is to fix the OOM problem on X86 > with 24TB memory which allocates memory in late initialisation. > But for Power platform with 32TB memory, it causes a call trace > in vfs_caches_init->inode_init() and inode hash table needs more > memory. > So this patch allocates 1GB for 0.25TB/node for large system > as it is mentioned in https://lkml.org/lkml/2015/5/1/627 > > This call trace is found on Power with 32TB memory, 1024CPUs, 16nodes. > Currently, it only allocates 2GB*16=32GB for early initialisation. But > Dentry cache hash table needes 16GB and Inode cache hash table needs > 16GB. So the system have no enough memory for it. > The log from dmesg as the following: > > Dentry cache hash table entries: 2147483648 (order: 18,17179869184 bytes) > vmalloc: allocation failure, allocated 16021913600 of 17179934720 bytes > swapper/0: page allocation failure: order:0,mode:0x2080020 > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.0-0-ppc64 > Call Trace: > [c0000000012bfa00] [c0000000007c4a50].dump_stack+0xb4/0xb664 (unreliable) > [c0000000012bfa80] [c0000000001f93d4].warn_alloc_failed+0x114/0x160 > [c0000000012bfb30] [c00000000023c204].__vmalloc_area_node+0x1a4/0x2b0 > [c0000000012bfbf0] [c00000000023c3f4].__vmalloc_node_range+0xe4/0x110 > [c0000000012bfc90] [c00000000023c460].__vmalloc_node+0x40/0x50 > [c0000000012bfd10] [c000000000b67d60].alloc_large_system_hash+0x134/0x2a4 > [c0000000012bfdd0] [c000000000b70924].inode_init+0xa4/0xf0 > [c0000000012bfe60] [c000000000b706a0].vfs_caches_init+0x80/0x144 > [c0000000012bfef0] [c000000000b35208].start_kernel+0x40c/0x4e0 > [c0000000012bff90] [c000000000008cfc]start_here_common+0x20/0x4a4 > Mem-Info: > > Acked-by: Mel Gorman > Signed-off-by: Li Zhang Acked-by: Vlastimil Babka