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Subject: Re: [RFC 34/43] shmem: PKRAM: multithread preserving and restoring
 shmem pages
To:     Anthony Yznaga <anthony.yznaga@oracle.com>, linux-mm@kvack.org,
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From:   Randy Dunlap <rdunlap@infradead.org>
Message-ID: <4e44858d-a416-696e-0d65-0b5ca8836b7d@infradead.org>
Date:   Thu, 7 May 2020 09:30:55 -0700
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On 5/6/20 5:42 PM, Anthony Yznaga wrote:
> Improve performance by multithreading the work to preserve and restore
> shmem pages.
> 
> Add 'pkram_max_threads=' kernel option to specify the maximum number
> of threads to use to preserve or restore the pages of a shmem file.
> The default is 16.

Hi,
Please document kernel boot options in Documentation/admin-guide/kernel-parameters.txt.

> When preserving pages each thread saves chunks of a file to a pkram_obj
> until no more no more chunks are available.
> 
> When restoring pages each thread loads pages using a copy of a
> pkram_stream initialized by pkram_prepare_load_obj(). Under the hood
> each thread ends up fetching and operating on pkram_link pages.
> 
> Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
> ---
>  include/linux/pkram.h |   2 +
>  mm/shmem_pkram.c      | 101 +++++++++++++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 101 insertions(+), 2 deletions(-)

thanks.
-- 
~Randy