[dpdk-dev] [PATCH v2 1/1] doc: correct Vhost Sample Application guide

Xie, Huawei huawei.xie at intel.com
Thu Dec 10 14:33:53 CET 2015



> -----Original Message-----
> From: Iremonger, Bernard
> Sent: Thursday, December 10, 2015 9:20 PM
> To: Xie, Huawei; Yuanhan Liu
> Cc: dev at dpdk.org
> Subject: RE: [dpdk-dev] [PATCH v2 1/1] doc: correct Vhost Sample
> Application guide
> 
> Hi Huawei,
> 
> <snip>
> 
> > > > I don't think that's a right "correction": vhost-swtich would fail
> > > > to
> > > > start:
> > > >
> > > >     EAL: Error - exiting with code: 1
> > > >     Cause: Cannot create mbuf pool
> > > >
> > > > As vhost-switch creates more mbuf than 1024M can hold.
> > > >
> > > > However, I do think that adding this option is necessary, otherwise,
> > > > all hugepages will be allocated to vhost-switch, leaving no memory
> > > > for
> > > starting
> > > > VM at all. (And this is kind of informatin you need to put into
> > > > commit
> > > log).
> > > >
> > > > And limiting it to "1024M" is reasonable as well, so that we can run
> > > > it
> > > on a
> > > > desktop (or laptop) without too many memories. You just need fix
> > > > vhost- switch example to not allocate too many mbufs by default.
> > > >
> > > > 	--yliu
> > >
> > > Yes the --socket-mem  <number> option is necessary.
> > > I will add a note that a value of  <number> may need to be greater
> > > than 1024.
> > > I will submit a patch to vhost-switch to reduce the number of mbufs.
> > >
> > I recall we have to allocate mbufs for each queue rather than used queues
> > only, so memory consumption depends on queue number. After that issue is
> > fixed, I think 1024MB is enough. For the time being, you could
> temporarily
> > use 2048M and add an explanation.
> >
> 
> I have sent a v3 of this patch which includes a note that the value of 1024
> may have to be increased.
> I would prefer to keep the value of 1024.
> 
For FVL with more queues, I recall 1024mb isn't enough, but it is ok with a note. :).
> Regards,
> 
> Bernard.



More information about the dev mailing list