From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH v2 2/2] memalloc: do not use lockfiles for
	single file segments mode
Date: Tue, 02 Apr 2019 16:08:24 +0200
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References: <728c19fa1ed26cdd319fe65e23c4058363dbf2dd.1553882085.git.anatoly.burakov@intel.com>
 <2b5404285e5ddc460a857cc90130db1b2c717dfc.1553882085.git.anatoly.burakov@intel.com>
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Cc: dev@dpdk.org, John McNamara <john.mcnamara@intel.com>,
 Marko Kovacevic <marko.kovacevic@intel.com>, david.marchand@redhat.com,
 maxime.coquelin@redhat.com
To: Anatoly Burakov <anatoly.burakov@intel.com>
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29/03/2019 18:55, Anatoly Burakov:
> Due to internal glibc limitations [1], DPDK may exhaust internal
> file descriptor limits when using smaller page sizes, which results
> in inability to use system calls such as select() by user
> applications.
> 
> Single file segments option stores lock files per page to ensure
> that pages are deleted when there are no more users, however this
> is not necessary because the processes will be holding onto the
> pages anyway because of mmap(). Thus, removing pages from the
> filesystem is safe even though they may be used by some other
> secondary process. As a result, single file segments mode no
> longer stores inordinate amounts of segment fd's, and the above
> issue with fd limits is solved.
> 
> However, this will not work for legacy mem mode. For that, simply
> document that using bigger page sizes is the only option.
> 
> [1] https://mails.dpdk.org/archives/dev/2019-February/124386.html
> 
> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>

Applied, thanks