From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bruce Richardson <bruce.richardson@intel.com>
Subject: Re: Unlinking hugepage backing file after initialiation
Date: Tue, 29 Sep 2015 12:14:28 +0100
Message-ID: <20150929111428.GB6748@bricha3-MOBL3>
References: <D22F2383.2219C%shesha@cisco.com>
 <2601191342CEEE43887BDE71AB97725836AA13EA@irsmsx105.ger.corp.intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Cc: "dev@dpdk.org" <dev@dpdk.org>
To: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>
Return-path: <dev-bounces@dpdk.org>
Received: from mga14.intel.com (mga14.intel.com [192.55.52.115])
 by dpdk.org (Postfix) with ESMTP id 7868D3787
 for <dev@dpdk.org>; Tue, 29 Sep 2015 13:14:32 +0200 (CEST)
Content-Disposition: inline
In-Reply-To: <2601191342CEEE43887BDE71AB97725836AA13EA@irsmsx105.ger.corp.intel.com>
List-Id: patches and discussions about DPDK <dev.dpdk.org>
List-Unsubscribe: <http://dpdk.org/ml/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <http://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
Sender: "dev" <dev-bounces@dpdk.org>

On Tue, Sep 29, 2015 at 09:03:15AM +0000, Ananyev, Konstantin wrote:
> 
> 
> > -----Original Message-----
> > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of shesha Sreenivasamurthy (shesha)
> > Sent: Tuesday, September 29, 2015 1:04 AM
> > To: dev@dpdk.org
> > Subject: [dpdk-dev] Unlinking hugepage backing file after initialiation
> > 
> > Hello,
> > As of DPDK2.1, backing files are created in hugetablefs during mapping (in eal_memory.c::rte_eal_hugepage_init()) and these files are
> > not cleaned up (unlinked) after initialization (mmap-ing). This means, when the application crashes or stopped, the memory is still
> > consumed. Therefore, is there any reason not to unlink backing files after initialization 
> 
> For secondary process(es) to be able to open/map them too?
> Konstantin
> 

Exactly. The hugepages are kept present on the file system so that secondary
processes can use them to attach to a primary process memory in a multi-process
setup.
What is done instead is that any old hugepage files are cleaned up when the
application starts (or restarts).

Regards,
/Bruce

> >? If no, I will send a patch for the change.
> > 
> > --
> > - Thanks
> > char * (*shesha) (uint64_t cache, uint8_t F00D)
> > { return 0x0000C0DE; }