From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f173.google.com (mail-pf0-f173.google.com [209.85.192.173]) by kanga.kvack.org (Postfix) with ESMTP id B73246B0009 for ; Tue, 2 Feb 2016 09:43:33 -0500 (EST) Received: by mail-pf0-f173.google.com with SMTP id w123so13590936pfb.0 for ; Tue, 02 Feb 2016 06:43:33 -0800 (PST) Received: from mail-pa0-x22a.google.com (mail-pa0-x22a.google.com. [2607:f8b0:400e:c03::22a]) by mx.google.com with ESMTPS id p11si2337912par.72.2016.02.02.06.43.32 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 02 Feb 2016 06:43:32 -0800 (PST) Received: by mail-pa0-x22a.google.com with SMTP id yy13so99932451pab.3 for ; Tue, 02 Feb 2016 06:43:32 -0800 (PST) Date: Tue, 2 Feb 2016 23:41:40 +0900 From: Sergey Senozhatsky Subject: Re: [REGRESSION] [BISECTED] kswapd high CPU usage Message-ID: <20160202144140.GA460@swordfish> References: <20160121161656.GA16564@node.shutemov.name> <20160125103853.GD11095@node.shutemov.name> <20160202135950.GA5026@node.shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160202135950.GA5026@node.shutemov.name> Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: Hugh Greenberg , Andrea Arcangeli , Mel Gorman , Vlastimil Babka , Rik van Riel , Minchan Kim , Nitin Gupta , Sergey Senozhatsky , linux-mm@kvack.org, Andrew Morton , Seth Jennings On (02/02/16 15:59), Kirill A. Shutemov wrote: > > > On Sat, Jan 23, 2016 at 03:57:21PM +0000, Hugh Greenberg wrote: > > > > Kirill A. Shutemov shutemov.name> writes: > > > > > > > > > > Could you try to insert > > "late_initcall(set_recommended_min_free_kbytes);" > > > > > back and check if makes any difference. > > > > > > > > > > > > > We tested adding late_initcall(set_recommended_min_free_kbytes); > > > > back in 4.1.14 and it made a huge difference. We aren't sure if the > > > > issue is 100% fixed, but it could be. We will keep testing it. > > > > > > It would be nice to have values of min_free_kbytes before and after > > > set_recommended_min_free_kbytes() in your configuration. > > > > > > > Before adding set_recommended_min_free_kbytes: 5391 > > After: 67584 > > [ add more people to the thread ] > > The 'before' value look low to me for machine with 2G of RAM. > > In the bugzilla[1], you've mentioned zram. I wounder if we need to > increase min_free_kbytes when zram is in use as we do for THP. > > [1] https://bugzilla.kernel.org/show_bug.cgi?id=110501 [add Seth Jennings] additional info: http://marc.info/?l=linux-mm&m=145373987224270 > The reports are coming from 2GB Haswell chromebooks. I have a 4GB haswell > chromebook and I cannot reproduce the issue, even if I boot the kernel with > 2GB or less. > > After more testing, we were still able to reproduce the issue. It seems to > have taken longer to show up this time. a small note, I assume, IF min_free_kbytes must be set then probably in zsmalloc (zbud?) init, not in zram. zswap can use both -- zsmalloc and zbud. -ss -- 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