On Wed, Sep 17, 2014 at 11:01:40AM +0100, Bruce Richardson wrote: > To improve performance by using bulk alloc or vectored RX routines, we > need to set rx free threshold (rxfreet) value to 32, so make this the > testpmd default. > > Signed-off-by: Bruce Richardson <bruce.richardson at intel.com> > --- > app/test-pmd/testpmd.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c > index 9f6cdc4..5751607 100644 > --- a/app/test-pmd/testpmd.c > +++ b/app/test-pmd/testpmd.c > @@ -225,7 +225,7 @@ 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 > */ >
Why 32? Was that an experimentally determined value? Does it hold true for all PMD's?