From: Izik Eidus <izik.eidus@ravellosystems.com>
To: Ni zhan Chen <nizhan.chen@gmail.com>
Cc: Linux Memory Management List <linux-mm@kvack.org>,
Andrea Arcangeli <aarcange@redhat.com>,
Petr Holasek <pholasek@redhat.com>,
Hugh Dickins <hughd@google.com>,
Chris Wright <chrisw@sous-sol.org>,
Rik van Riel <riel@redhat.com>
Subject: Re: ksm questions
Date: Wed, 24 Oct 2012 14:02:43 +0200 [thread overview]
Message-ID: <5087D8E3.6090900@ravellosystems.com> (raw)
In-Reply-To: <5087D817.7070106@gmail.com>
On 10/24/2012 01:59 PM, Ni zhan Chen wrote:
> On 10/24/2012 07:46 PM, Izik Eidus wrote:
>> 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 Izik, what about the other three questions?
Question number 2 is beacuse it is forced to work with anonymous pages,
about question 3 - I will have to remember why from the very begining I
wrote it to support only anonymous pages (few years have been passed),
maybe Andrea/Huge have it more hot in their heads?
>
>>
>>>
>>> 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: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2012-10-24 12:02 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-24 11:19 Ni zhan Chen
2012-10-24 11:46 ` Izik Eidus
2012-10-24 11:59 ` Ni zhan Chen
2012-10-24 12:02 ` Izik Eidus [this message]
2012-10-24 12:16 ` Ni zhan Chen
2012-10-24 12:20 ` Izik Eidus
2012-10-24 12:35 ` Ni zhan Chen
2012-10-24 12:40 ` Ni zhan Chen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5087D8E3.6090900@ravellosystems.com \
--to=izik.eidus@ravellosystems.com \
--cc=aarcange@redhat.com \
--cc=chrisw@sous-sol.org \
--cc=hughd@google.com \
--cc=linux-mm@kvack.org \
--cc=nizhan.chen@gmail.com \
--cc=pholasek@redhat.com \
--cc=riel@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox