Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757593Ab3CNMj3 (ORCPT ); Thu, 14 Mar 2013 08:39:29 -0400 Received: from mail-ob0-f176.google.com ([209.85.214.176]:47603 "EHLO mail-ob0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750989Ab3CNMj2 (ORCPT ); Thu, 14 Mar 2013 08:39:28 -0400 MIME-Version: 1.0 In-Reply-To: <513A9AF7.4020909@gmail.com> References: <51347A6E.8010608@iskon.hr> <513A9AF7.4020909@gmail.com> Date: Thu, 14 Mar 2013 20:39:27 +0800 Message-ID: Subject: Re: Inactive memory keep growing and how to release it? From: Hillf Danton To: Will Huck Cc: Lenky Gao , Zlatko Calusic , Greg KH , "linux-kernel@vger.kernel.org" , "devel@linuxdriverproject.org" , "olaf@aepfle.de" , Linux-MM , Hugh Dickins , Mel Gorman , Rik van Riel Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2981 Lines: 92 On Sat, Mar 9, 2013 at 10:14 AM, Will Huck wrote: > Cc experts. Hugh, Johannes, > > On 03/04/2013 08:21 PM, Lenky Gao wrote: >> >> 2013/3/4 Zlatko Calusic : >>> >>> The drop_caches mechanism doesn't free dirty page cache pages. And your >>> bash >>> script is creating a lot of dirty pages. Run it like this and see if it >>> helps your case: >>> >>> sync; echo 3 > /proc/sys/vm/drop_caches >> >> Thanks for your advice. >> >> The inactive memory still cannot be reclaimed after i execute the sync >> command: >> >> # cat /proc/meminfo | grep Inactive\(file\); >> Inactive(file): 882824 kB >> # sync; >> # echo 3 > /proc/sys/vm/drop_caches >> # cat /proc/meminfo | grep Inactive\(file\); >> Inactive(file): 777664 kB >> >> I find these page becomes orphaned in this function, but do not understand >> why: >> >> /* >> * If truncate cannot remove the fs-private metadata from the page, the >> page >> * becomes orphaned. It will be left on the LRU and may even be mapped >> into >> * user pagetables if we're racing with filemap_fault(). >> * >> * We need to bale out if page->mapping is no longer equal to the >> original >> * mapping. This happens a) when the VM reclaimed the page while we >> waited on >> * its lock, b) when a concurrent invalidate_mapping_pages got there >> first and >> * c) when tmpfs swizzles a page between a tmpfs inode and swapper_space. >> */ >> static int >> truncate_complete_page(struct address_space *mapping, struct page *page) >> { >> ... >> >> My file system type is ext3, mounted with the opteion data=journal and >> it is easy to reproduce. >> Perhaps we have to consider page count for orphan page if it could be reproduced with mainline. Hillf --- --- a/mm/vmscan.c Sun Mar 10 13:36:26 2013 +++ b/mm/vmscan.c Thu Mar 14 20:29:40 2013 @@ -315,14 +315,14 @@ out: return ret; } -static inline int is_page_cache_freeable(struct page *page) +static inline int is_page_cache_freeable(struct page *page, int has_mapping) { /* * A freeable page cache page is referenced only by the caller * that isolated the page, the page cache radix tree and * optional buffer heads at page->private. */ - return page_count(page) - page_has_private(page) == 2; + return page_count(page) - page_has_private(page) == has_mapping + 1; } static int may_write_to_queue(struct backing_dev_info *bdi, @@ -393,7 +393,7 @@ static pageout_t pageout(struct page *pa * swap_backing_dev_info is bust: it doesn't reflect the * congestion state of the swapdevs. Easy to fix, if needed. */ - if (!is_page_cache_freeable(page)) + if (!is_page_cache_freeable(page, mapping ? 1 : 0)) return PAGE_KEEP; if (!mapping) { /* -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/