Mike has the best point, I think. 30 seconds between sends will cause the congestion window to close. Depending on what is in use (CUBIC vs. Reno), this will change behavior.
-- Todd On Wed, Apr 12, 2017 at 3:27 PM, Greg Young <[email protected]> wrote: > You are likely measuring wrong and just have not figured out how yet. > > On Wed, Apr 12, 2017 at 8:56 PM, J Crawford <[email protected]> > wrote: > > The SO question has the source codes of a simple server and client that > > demonstrate and isolate the problem. Basically I'm timing the latency of > a > > ping-pong (client-server-client) message. I start by sending one message > > every 1 millisecond. I wait for 200k messages to be sent so that the > HotSpot > > has a chance to optimize the code. Then I change my pause time from 1 > > millisecond to 30 seconds. For my surprise my write and read operation > > become considerably slower. > > > > I don't think it is a JIT/HotSpot problem. I was able to pinpoint the > slower > > method to the native JNI calls to write (write0) and read. Even if I > change > > the pause from 1 millisecond to 1 second, problem persists. > > > > I was able to observe that on MacOS and Linux. > > > > Does anyone here have a clue of what can be happening? > > > > Note that I'm disabling Nagle's Algorithm with setTcpNoDelay(true). > > > > SO question with code and output: > > http://stackoverflow.com/questions/43377600/ > socketchannel-why-if-i-write-msgs-quickly-the-latency-of- > each-message-is-low-b > > > > Thanks! > > > > -JC > > > > -- > > You received this message because you are subscribed to the Google Groups > > "mechanical-sympathy" group. > > To unsubscribe from this group and stop receiving emails from it, send an > > email to [email protected]. > > For more options, visit https://groups.google.com/d/optout. > > > > -- > Studying for the Turing test > > -- > You received this message because you are subscribed to the Google Groups > "mechanical-sympathy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "mechanical-sympathy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
