On Mon, Jul 20, 2020 at 10:55 AM Jason Wang <jasowang@xxxxxxxxxx> wrote: > > > On 2020/7/17 上午1:16, Eugenio Perez Martin wrote: > > On Fri, Jul 10, 2020 at 7:58 AM Michael S. Tsirkin <mst@xxxxxxxxxx> wrote: > >> On Fri, Jul 10, 2020 at 07:39:26AM +0200, Eugenio Perez Martin wrote: > >>>>> How about playing with the batch size? Make it a mod parameter instead > >>>>> of the hard coded 64, and measure for all values 1 to 64 ... > >>>> > >>>> Right, according to the test result, 64 seems to be too aggressive in > >>>> the case of TX. > >>>> > >>> Got it, thanks both! > >> In particular I wonder whether with batch size 1 > >> we get same performance as without batching > >> (would indicate 64 is too aggressive) > >> or not (would indicate one of the code changes > >> affects performance in an unexpected way). > >> > >> -- > >> MST > >> > > Hi! > > > > Varying batch_size as drivers/vhost/net.c:VHOST_NET_BATCH, > > > Did you mean varying the value of VHOST_NET_BATCH itself or the number > of batched descriptors? > > > > and testing > > the pps as previous mail says. This means that we have either only > > vhost_net batching (in base testing, like previously to apply this > > patch) or both batching sizes the same. > > > > I've checked that vhost process (and pktgen) goes 100% cpu also. > > > > For tx: Batching decrements always the performance, in all cases. Not > > sure why bufapi made things better the last time. > > > > Batching makes improvements until 64 bufs, I see increments of pps but like 1%. > > > > For rx: Batching always improves performance. It seems that if we > > batch little, bufapi decreases performance, but beyond 64, bufapi is > > much better. The bufapi version keeps improving until I set a batching > > of 1024. So I guess it is super good to have a bunch of buffers to > > receive. > > > > Since with this test I cannot disable event_idx or things like that, > > what would be the next step for testing? > > > > Thanks! > > > > -- > > Results: > > # Buf size: 1,16,32,64,128,256,512 > > > > # Tx > > # === > > # Base > > 2293304.308,3396057.769,3540860.615,3636056.077,3332950.846,3694276.154,3689820 > > > What's the meaning of buf size in the context of "base"? > Hi Jason. I think that all the previous questions have been answered in the response to MST, please let me know if I missed something. > And I wonder maybe perf diff can help. Great, I will run it too. Thanks! > > Thanks > > > > # Batch > > 2286723.857,3307191.643,3400346.571,3452527.786,3460766.857,3431042.5,3440722.286 > > # Batch + Bufapi > > 2257970.769,3151268.385,3260150.538,3379383.846,3424028.846,3433384.308,3385635.231,3406554.538 > > > > # Rx > > # == > > # pktgen results (pps) > > 1223275,1668868,1728794,1769261,1808574,1837252,1846436 > > 1456924,1797901,1831234,1868746,1877508,1931598,1936402 > > 1368923,1719716,1794373,1865170,1884803,1916021,1975160 > > > > # Testpmd pps results > > 1222698.143,1670604,1731040.6,1769218,1811206,1839308.75,1848478.75 > > 1450140.5,1799985.75,1834089.75,1871290,1880005.5,1934147.25,1939034 > > 1370621,1721858,1796287.75,1866618.5,1885466.5,1918670.75,1976173.5,1988760.75,1978316 > > > > pktgen was run again for rx with 1024 and 2048 buf size, giving > > 1988760.75 and 1978316 pps. Testpmd goes the same way. > > >
