Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1642679

Re: [PATCH RFC] hugetlbfs 'noautofill' mount option

From Prakash Sangappa <prakash.sangappa@oracle.com>
Newsgroups linux.kernel
Subject Re: [PATCH RFC] hugetlbfs 'noautofill' mount option
Date 2017-05-16 19:00 +0200
Message-ID <tHNZg-84e-17@gated-at.bofh.it> (permalink)
References (5 earlier) <tD7OW-13Q-19@gated-at.bofh.it> <tETeN-5QP-7@gated-at.bofh.it> <tEZax-1o3-11@gated-at.bofh.it> <tF99T-7Or-5@gated-at.bofh.it> <tFkym-7gI-15@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw



On 5/9/17 1:59 PM, Prakash Sangappa wrote:
>
>
> On 5/9/17 1:58 AM, Christoph Hellwig wrote:
>> On Mon, May 08, 2017 at 03:12:42PM -0700, prakash.sangappa wrote:
>>> Regarding #3 as a general feature, do we want to
>>> consider this and the complexity associated with the
>>> implementation?
>> We have to.  Given that no one has exclusive access to hugetlbfs
>> a mount option is fundamentally the wrong interface.
>
>
> A hugetlbfs filesystem may need to be mounted for exclusive use by
> an application. Note, recently the 'min_size' mount option was added
> to hugetlbfs, which would reserve minimum number of huge pages
> for that filesystem for use by an application. If the filesystem with
> min size specified, is not setup for exclusive use by an application,
> then the purpose of reserving huge pages is defeated.  The
> min_size option was for use by applications like the database.
>
> Also, I am investigating enabling hugetlbfs mounts within user
> namespace's mount namespace. That would allow an application
> to mount a hugetlbfs filesystem inside a namespace exclusively for
> its use, running as a non root user. For this it seems like the 
> 'min_size'
> should be subject to some user limits. Anyways, mounting inside
> user namespaces is  a different discussion.
>
> So, if a filesystem has to be setup for exclusive use by an application,
> then different mount options can be used for that filesystem.
>

Any further comments?

Cc'ing Andrea as we had discussed this requirement for the Database.

Back to linux.kernel | Previous | Next | Find similar | Unroll thread


Thread

Re: [PATCH RFC] hugetlbfs 'noautofill' mount option Prakash Sangappa <prakash.sangappa@oracle.com> - 2017-05-16 19:00 +0200

csiph-web