[dpdk-dev] [PATCH v2 1/5] mem: add --single-file to create single mem-backed file

[Traynor, Kevin]

> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Thomas Monjalon
> Sent: Tuesday, March 8, 2016 10:31 AM
> To: dev at dpdk.org
> Cc: nakajima.yoshihiro at lab.ntt.co.jp; mst at redhat.com; p.fedin at samsung.com;
> ann.zhuangyanying at huawei.com
> Subject: Re: [dpdk-dev] [PATCH v2 1/5] mem: add --single-file to create
> single mem-backed file
> 
> 2016-03-08 17:04, Yuanhan Liu:
> > On Tue, Mar 08, 2016 at 10:49:30AM +0200, Panu Matilainen wrote:
> > > On 03/07/2016 03:13 PM, Yuanhan Liu wrote:
> > > >To me, maybe you could base the SINGLE_FILE_SEGMENTS option, and add
> > > >another option, say --no-sort (I confess this name sucks, but you get
> > > >my point). With that, we could make sure to create as least huge page
> > > >files as possible, to fit your case.
> > >
> > > Note that SINGLE_FILE_SEGMENTS is a nasty hack that only the IVSHMEM
> config
> > > uses, getting rid of it (by replacing with a runtime switch) would be
> great.
> >
> > Can't agree more.
> 
> +1
> 
> > BTW, FYI, Jianfeng and I had a private talk, and we came to agree that
> > it might be better to handle it outside the normal huge page init stage,
> > just like this patch does, but adding the support of multiple huge page
> > sizes. Let's not add more messy code there.
> >
> > 	--yliu
> >
> > > OTOH IVSHMEM itself seems to have fallen out of the fashion since the
> memnic
> > > driver is unmaintained and broken since dpdk 2.0... CC'ing the IVSHMEM
> > > maintainer in case he has thoughts on this.
> 
> The ivshmem config was not used for memnic which was using ivshmem only for
> data path.
> CONFIG_RTE_LIBRTE_IVSHMEM and CONFIG_RTE_EAL_SINGLE_FILE_SEGMENTS are more
> about full memory sharing.
> I have the feeling it could be dropped.
> It there are some users, I'd like to see a justification and a rework to
> remove these build options.

Just to clarify - is this suggesting the removal of the IVSHMEM library itself,
or just some of the config options?

The reason I ask is that although we don't currently use it in OVS with DPDK,
I've seen at least one person using it in conjunction with the ring interface.
There may be others, so I want to cross-post if there's a deprecation discussion. 

Kevin.