From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx109.postini.com [74.125.245.109]) by kanga.kvack.org (Postfix) with SMTP id D9D206B0072 for ; Wed, 24 Oct 2012 07:46:27 -0400 (EDT) Received: by mail-ee0-f71.google.com with SMTP id c13so360987eek.2 for ; Wed, 24 Oct 2012 04:46:26 -0700 (PDT) Message-ID: <5087D50D.8000101@ravellosystems.com> Date: Wed, 24 Oct 2012 13:46:21 +0200 From: Izik Eidus MIME-Version: 1.0 Subject: Re: ksm questions References: <5087CED1.2030307@gmail.com> In-Reply-To: <5087CED1.2030307@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Ni zhan Chen Cc: Linux Memory Management List , Andrea Arcangeli , Petr Holasek , Hugh Dickins , Chris Wright , Rik van Riel On 10/24/2012 01:19 PM, Ni zhan Chen wrote: > Hi all, > > I have some questions about ksm. > > 1) khugepaged default nice value is 19, but ksmd default nice value is > 5, why this big different? > 2) why ksm doesn't support pagecache and tmpfs now? What's the > bottleneck? > 3) ksm kernel doc said that "KSM only merges anonymous(private) pages, > never pagecache(file) pages". But where judege it should be private? > 4) ksm kernel doc said that "To avoid the instability and the > resulting false negatives to be permanent, KSM re-initializes the > unstable tree root node to an empty tree, at every KSM pass." But I > can't find where re-initializes the unstable tree, could you explain me? in scan_get_next_rmap_item(), if (slot == &ksm_mm_head) then we do root_unstable_tree = RB_ROOT; this will result in root_unstable_tree being empty. > > Thanks in advance. :-) > > Regards, > Chen > -- 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