From: Vlastimil Babka <vbabka@suse.cz>
To: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Michal Hocko <mhocko@suse.com>,
Mel Gorman <mgorman@techsingularity.net>,
Johannes Weiner <hannes@cmpxchg.org>,
"Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>,
Minchan Kim <minchan@kernel.org>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Linux API <linux-api@vger.kernel.org>
Subject: Re: [PATCH] mm/page_alloc: don't reserve ZONE_HIGHMEM for ZONE_MOVABLE request
Date: Tue, 29 Aug 2017 09:00:16 +0200 [thread overview]
Message-ID: <ad269513-56e4-87af-f44d-86a5dba1c9f6@suse.cz> (raw)
In-Reply-To: <20170829003657.GC14489@js1304-P5Q-DELUXE>
On 08/29/2017 02:36 AM, Joonsoo Kim wrote:
> On Mon, Aug 28, 2017 at 08:45:07AM +0200, Vlastimil Babka wrote:
>> +CC linux-api
>>
>> On 08/28/2017 02:28 AM, Joonsoo Kim wrote:
>>> On Fri, Aug 25, 2017 at 09:56:10AM +0200, Vlastimil Babka wrote:
>>>
>>> Seems reasonable. However, if there is a user who checks
>>> sysctl_lowmem_reserve_ratio entry for HIGHMEM and change it, suggested
>>> interface will cause a problem since it doesn't expose ratio for
>>> HIGHMEM. Am I missing something?
>>
>> As you explained, it makes little sense to change it for HIGHMEM which
>> only affects MOVABLE allocations. Also I doubt there are many systems
>> with both HIGHMEM (implies 32bit) *and* MOVABLE (implies NUMA, memory
>> hotplug...) zones. So I would just remove it, and if somebody will
>> really miss it, we can always add it back. In any case, please CC
>> linux-api on the next version.
>
> If we will accept a change that potentially breaks the user, I think
> that making zero as a special value for sysctl_lowmem_reserve_ratio
> is better solution. How about this way?
I'd prefer removal, but won't object to zero. Certainly much better than
UINT_MAX.
> Thanks.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-api" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
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:[~2017-08-29 7:00 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1503553546-27450-1-git-send-email-iamjoonsoo.kim@lge.com>
[not found] ` <e919c65e-bc2f-6b3b-41fc-3589590a84ac@suse.cz>
[not found] ` <20170825002031.GD29701@js1304-P5Q-DELUXE>
[not found] ` <d57eeb5c-d91d-9718-8473-3c6db465b154@suse.cz>
[not found] ` <20170828002857.GB9167@js1304-P5Q-DELUXE>
2017-08-28 6:45 ` [PATCH] mm/page_alloc: don't reserve ZONE_HIGHMEM for ZONE_MOVABLE request Vlastimil Babka
[not found] ` <78dd0160-14e8-22a6-bd10-d37bbd39f77b-AlSwsSmVLrQ@public.gmane.org>
2017-08-29 0:36 ` Joonsoo Kim
2017-08-29 7:00 ` Vlastimil Babka [this message]
[not found] <1504672525-17915-1-git-send-email-iamjoonsoo.kim@lge.com>
2017-09-06 7:54 ` Vlastimil Babka
2017-09-14 13:24 ` Michal Hocko
2018-04-04 0:24 ` Joonsoo Kim
2018-04-12 12:01 ` Michal Hocko
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=ad269513-56e4-87af-f44d-86a5dba1c9f6@suse.cz \
--to=vbabka@suse.cz \
--cc=akpm@linux-foundation.org \
--cc=aneesh.kumar@linux.vnet.ibm.com \
--cc=hannes@cmpxchg.org \
--cc=iamjoonsoo.kim@lge.com \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@techsingularity.net \
--cc=mhocko@suse.com \
--cc=minchan@kernel.org \
/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;
as well as URLs for NNTP newsgroup(s).