On Wed, 2014-08-27 at 15:17 -0400, Ted Ross wrote: > > On 08/27/2014 03:05 PM, Andrew Stitcher wrote: > > On Wed, 2014-08-27 at 14:55 -0400, Andrew Stitcher wrote: > >> ... > >> Of this only applies under the exact circumstances of these tests, until > >> we have more data points. I'd suspect it must also depend on the message > >> size too. > >> > > > > Just to reply to myself... > > > > Keeping the credit window at around the MTU size is going to give you > > the most efficient networking transfers. > > I'm not sure I'm following you here. Credits are in units of messages > whereas MTU is in octets. > > To avoid bad interactions with the Nagle algorithm in TCP, the credit > window multiplied by message size should exceed MTU (Maybe that was the > point you were originally making).
Not clear enough - (fuzzy thinking today) - what I'm really trying to say is that for efficient transfers you want the packets to be full, so the credit should be high enough so that credit * msg size > MTU. But, as you say, the latency is just as important too. s\So actually I should have really been pointing out that the aim is to fill the bandwidth-delay product, so that you send new messages before the messages in the pipeline run out. Andrew
