From: Oscar Salvador <osalvador@suse.de>
To: Michal Hocko <mhocko@suse.com>
Cc: david@redhat.com, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, vbabka@suse.cz, pasha.tatashin@soleen.com
Subject: Re: [RFC PATCH v2 3/4] mm,memory_hotplug: Add mhp_supports_memmap_on_memory
Date: Mon, 30 Nov 2020 09:50:22 +0100 [thread overview]
Message-ID: <20201130085018.GA3825@linux> (raw)
In-Reply-To: <20201127150253.GU31550@dhcp22.suse.cz>
On Fri, Nov 27, 2020 at 04:02:53PM +0100, Michal Hocko wrote:
> It should also require a tunable (kernel parameter for now but maybe we
> will need a more fine grained control later) to enable this explicitly.
> Earlier discussions have pointed out that allocating vmemmap from each
> section can lead to a sparse memory unsuitable for very large pages.
> So I believe this should be an opt in.
Yeah, I already had that in mind, just did not get to implement it in this RFC
yet as I was more focused on the implementation per se.
I thought about a tunable in /sys/device/system/memory/[file], but a kernel
command line boot option would also work and for the first implementation
would be less for a hassel.
> Also is there any reason why this cannot be a preparatory patch for the
> actual implementation? It would look more natural that way to me.
I guess you are right, will re-order it in a future submission.
--
Oscar Salvador
SUSE L3
next prev parent reply other threads:[~2020-11-30 8:50 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-25 11:20 [RFC PATCH v2 0/4] Allocate memmap from hotadded memory (per device) Oscar Salvador
2020-11-25 11:20 ` [RFC PATCH v2 1/4] mm,memory_hotplug: Introduce MHP_MEMMAP_ON_MEMORY Oscar Salvador
2020-11-27 14:59 ` Michal Hocko
2020-11-25 11:20 ` [RFC PATCH v2 2/4] mm,memory_hotplug: Allocate memmap from the added memory range Oscar Salvador
2020-11-27 15:15 ` Michal Hocko
2020-11-30 9:12 ` Oscar Salvador
2020-11-25 11:20 ` [RFC PATCH v2 3/4] mm,memory_hotplug: Add mhp_supports_memmap_on_memory Oscar Salvador
2020-11-27 15:02 ` Michal Hocko
2020-11-30 8:50 ` Oscar Salvador [this message]
2020-11-25 11:20 ` [RFC PATCH v2 4/4] mm,memory_hotplug: Enable MHP_MEMMAP_ON_MEMORY when supported Oscar Salvador
2020-11-27 11:55 ` Oscar Salvador
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=20201130085018.GA3825@linux \
--to=osalvador@suse.de \
--cc=david@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@suse.com \
--cc=pasha.tatashin@soleen.com \
--cc=vbabka@suse.cz \
/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).