Re: [dpdk-dev] Unlinking hugepage backing file after initialiation

["shesha Sreenivasamurthy (shesha)" <shesha@cisco.com>]

My bad that I said its not working, apologies.

Isn’t it correct to say that single process application do not benefit from having backing files ? In that case can make this configurable by passing a command line argument that will either unlink or keep the backing files, defaulting it to keeping the backing files. Single process application to do not need these files around can pass additional param to unlink these files ?

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

From: "Ananyev, Konstantin" <konstantin.ananyev@intel.com<mailto:konstantin.ananyev@intel.com>>
Date: Wednesday, September 30, 2015 at 2:53 PM
To: Cisco Employee <shesha@cisco.com<mailto:shesha@cisco.com>>, "dev@dpdk.org<mailto:dev@dpdk.org>" <dev@dpdk.org<mailto:dev@dpdk.org>>
Cc: "Michael S. Tsirkin" <mst@redhat.com<mailto:mst@redhat.com>>
Subject: RE: [dpdk-dev] Unlinking hugepage backing file after initialiation



-----Original Message-----
From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of shesha Sreenivasamurthy (shesha)
Sent: Wednesday, September 30, 2015 10:44 PM
To: dev@dpdk.org<mailto:dev@dpdk.org>
Cc: Michael S. Tsirkin
Subject: Re: [dpdk-dev] Unlinking hugepage backing file after initialiation
What I heard is the following: A multi-process DPDK application, working either in master-worker or master-slave fashion, can
potentially benefit by keeping the backing files in hugetlbfs. However, it is does not work today as the pages are cleaned and added
back when the application restarts.

Who says it is not working?
I admit that DPDK MP model is probably a bit constrained, but it does work.
It is probably good to read some docs:
http://dpdk.org/doc/guides/prog_guide/multi_proc_support.html
and/or look at the code that does MP support inside DPDK.
I think that might make things clearer.
Konstantin

On the other hand, for a single process application there is actually no benefit keeping the pages
around.
Therefore, I was wondering if we can make this configurable by passing a command line argument that will either unlink or keep the
backing files.
--
- Thanks
char * (*shesha) (uint64_t cache, uint8_t F00D)
{ return 0x0000C0DE; }
From: "Michael S. Tsirkin" <mst@redhat.com<mailto:mst@redhat.com><mailto:mst@redhat.com>>
Date: Tuesday, September 29, 2015 at 2:35 PM
To: Cisco Employee <shesha@cisco.com<mailto:shesha@cisco.com><mailto:shesha@cisco.com>>
Cc: "Xie, Huawei" <huawei.xie@intel.com<mailto:huawei.xie@intel.com><mailto:huawei.xie@intel.com>>, "dev@dpdk.org<mailto:dev@dpdk.org><mailto:dev@dpdk.org>"
<dev@dpdk.org<mailto:dev@dpdk.org><mailto:dev@dpdk.org>>
Subject: Re: [dpdk-dev] Unlinking hugepage backing file after initialiation
On Tue, Sep 29, 2015 at 05:50:00PM +0000, shesha Sreenivasamurthy (shesha) wrote:
Sure. Then, is there any real reason why the backing files should not be
unlinked ?
AFAIK qemu unlinks them already.
--
MST