Re: [dpdk-dev] [PATCH v2 3/5] testpmd: Change rxfreet default to 32

[Bruce Richardson <bruce.richardson@intel.com>]

On Fri, Nov 07, 2014 at 01:30:53PM +0100, Thomas Monjalon wrote:
> Hi Bruce,
> 
> 2014-09-24 09:03, Richardson, Bruce:
> > From: Neil Horman [mailto:nhorman@tuxdriver.com]
> > > On Tue, Sep 23, 2014 at 12:08:15PM +0100, Bruce Richardson wrote:
> > > > --- a/app/test-pmd/testpmd.c
> > > > +++ b/app/test-pmd/testpmd.c
> > > > @@ -225,7 +225,9 @@ struct rte_eth_thresh tx_thresh = {
> > > >  /*
> > > >   * Configurable value of RX free threshold.
> > > >   */
> > > > -uint16_t rx_free_thresh = 0; /* Immediately free RX descriptors by default. */
> > > > +uint16_t rx_free_thresh = 32; /* Refill RX descriptors once every 32 packets,
> > > > +		This setting is needed for ixgbe to enable bulk alloc or vector
> > > > +		receive functionality. */
> > > 
> > > I thought we were talking about making this a pmd private selectable item,
> > > or allowing a reserved "let the pmd decide" setting.  Or are we saving
> > > that for a later time?
> > 
> > Yes, we are looking at that - and hopefully we can also get a patch for that
> > in for our next release. However, I've left this patch in just in case that
> > doesn't actually happen, as the performance improvements for 10G are just
> > too good to leave aside for the sake of a 1-line change. Ideally, I'd like
> > this go to in, and then be replaced by a "proper" fix.
> 
> Now the patch for PMD defaults is integrated:
> 	http://dpdk.org/ml/archives/dev/2014-October/006511.html
> Are you working on getting these defaults in testpmd?
> 

Not at the minute, as I'm busy on other things. If I find time I can look at it,
though, if nobody else volunteers to do so first.

/Bruce


> Thanks
> -- 
> Thomas