From mboxrd@z Thu Jan  1 00:00:00 1970
From: "shesha Sreenivasamurthy (shesha)" <shesha@cisco.com>
Subject: Re: Unlinking hugepage backing file after initialiation
Date: Tue, 29 Sep 2015 14:03:59 +0000
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To: Bruce Richardson <bruce.richardson@intel.com>, "Ananyev, Konstantin"
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What do you mean by secondary process attaching to primary process (Master-=
slave setup ?) ? The first process crashed, how can we be sure that memory =
is not half written ?

--
- Thanks
char * (*shesha) (uint64_t cache, uint8_t F00D)
{ return 0x0000C0DE; }

From: Bruce Richardson <bruce.richardson@intel.com<mailto:bruce.richardson@=
intel.com>>
Organization: Intel Shannon Ltd.
Date: Tuesday, September 29, 2015 at 4:14 AM
To: "Ananyev, Konstantin" <konstantin.ananyev@intel.com<mailto:konstantin.a=
nanyev@intel.com>>
Cc: Cisco Employee <shesha@cisco.com<mailto:shesha@cisco.com>>, "dev@dpdk.o=
rg<mailto:dev@dpdk.org>" <dev@dpdk.org<mailto:dev@dpdk.org>>
Subject: Re: [dpdk-dev] Unlinking hugepage backing file after initialiation

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 Sreenivasamur=
thy (shesha)
> Sent: Tuesday, September 29, 2015 1:04 AM
> To: dev@dpdk.org<mailto: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 (i=
n eal_memory.c::rte_eal_hugepage_init()) and these files are
> not cleaned up (unlinked) after initialization (mmap-ing). This means, wh=
en the application crashes or stopped, the memory is still
> consumed. Therefore, is there any reason not to unlink backing files afte=
r 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 secondar=
y
processes can use them to attach to a primary process memory in a multi-pro=
cess
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; }