linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Qian Cai <cai@lca.pw>
To: "Guilherme G. Piccoli" <gpiccoli@canonical.com>
Cc: linux-mm@kvack.org, mike.kravetz@oracle.com,
	linux-kernel@vger.kernel.org, jay.vosburgh@canonical.com,
	kernel@gpiccoli.net
Subject: Re: [PATCH] hugetlb: Add nohugepages parameter to prevent hugepages creation
Date: Fri, 11 Oct 2019 19:35:57 -0400	[thread overview]
Message-ID: <36C2B5DF-7F21-42C6-BA77-6D86EDCB6BB3@lca.pw> (raw)
In-Reply-To: <20191011223955.1435-1-gpiccoli@canonical.com>



> On Oct 11, 2019, at 6:40 PM, Guilherme G. Piccoli <gpiccoli@canonical.com> wrote:
> 
> Kdump kernels won't benefit from hugepages - in fact it's quite opposite,
> it may be the case hugepages on kdump kernel can lead to OOM if kernel
> gets unable to allocate demanded pages due to the fact the preallocated
> hugepages are consuming a lot of memory.
> 
> This patch proposes a new kernel parameter to prevent the creation of
> HugeTLB hugepages - we currently don't have a way to do that. We can
> even have kdump scripts removing the kernel command-line options to
> set hugepages, but it's not straightforward to prevent sysctl/sysfs
> configuration, given it happens in later boot or anytime when the
> system is running.

Typically, kdump kernel has its own initramfs, and don’t even need to mount a rootfs, so I can’t see how sysfs/sysctl is relevant here.

  reply	other threads:[~2019-10-11 23:36 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-11 22:39 Guilherme G. Piccoli
2019-10-11 23:35 ` Qian Cai [this message]
2019-10-11 23:41   ` Guilherme Piccoli
2019-10-11 23:52     ` Qian Cai
2019-10-12  0:41       ` Guilherme Piccoli
2019-10-15 12:18         ` Michal Hocko
2019-10-15 13:58           ` Guilherme G. Piccoli
2019-10-15 14:05             ` Michal Hocko
2019-10-15 14:09               ` Guilherme G. Piccoli
2019-10-18 18:29                 ` Mike Kravetz
2019-10-24 16:21                   ` Guilherme G. Piccoli
2019-10-14 18:25 ` Mike Kravetz
2019-10-15  4:50   ` Guilherme G. Piccoli

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=36C2B5DF-7F21-42C6-BA77-6D86EDCB6BB3@lca.pw \
    --to=cai@lca.pw \
    --cc=gpiccoli@canonical.com \
    --cc=jay.vosburgh@canonical.com \
    --cc=kernel@gpiccoli.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mike.kravetz@oracle.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