This is a bit of a SWAG but you may be seeing effects of Nagle's algorithm. I believe the default for --tcp-nodelay changed to "on" sometime after your version. You may want to try that on both the client and broker side.
-Steve > -----Original Message----- > From: Toralf Lund [mailto:toralf.l...@pgs.com] > Sent: Wednesday, November 27, 2013 9:26 AM > To: users@qpid.apache.org > Subject: QPid 0.14 messaging times > > Hi. > > I'm testing pretty standard (I think) request-response type setup for > communication between two processes, using QPid 0.14 (AMQP 0.10). > Messaging is implemented via a the C++ Messaging API, and the broker is > qpidd from qpid-cpp-server. All running under CentOS 6.4. Messages are > typically quite small - contents are often just 2-3 bytes, but there are > couple > of headers as well. > > Question: What sort of transfer times should I expect for my setup? When > testing with all processes on the same machine, and a broker used > exclusively for this purpose, I get a round-trip time of up to 80 ms, or > slightly > more, which is a bit longer than I expected. Furthermore, closer inspection > seems to reveal that I get either of the following 4 > scenarios: > > 1. (Worst case) The request message takes around 40 ms to reach the > "server", and the response 40 ms to get back to the client - for a > total time of around 80 ms. > 2. The request message takes around 40 ms, but the response is very > fast, perhaps the transfer time is 1 ms or so. So the total time is > 40 ms or so. > 3. As above, only the other way around (fast request, slower response.) 4. > The request and response are both very fast, giving nearly > instantaneous feedback. > > 2 and 3 are the most common of these. > > So, is this as expected, or should I expect faster transfers? Where might the > 40 ms come from? > > I suppose I should provide some code here, but it will take a while to > prepare, so I thought I might ask some general questions first... > > As for QPid version, I'm using 0.14 simply because it seems to be the most > recent available on standard software depositories for the system, but > upgrading to a more recent release may of course be an option. > > Thanks, > > > - Toralf > > > This e-mail, including any attachments and response string, may contain > proprietary information which is confidential and may be legally privileged. > It > is for the intended recipient only. If you are not the intended recipient or > transmission error has misdirected this e-mail, please notify the author by > return e-mail and delete this message and any attachment immediately. If > you are not the intended recipient you must not use, disclose, distribute, > forward, copy, print or rely on this e-mail in any way except as permitted by > the author. --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@qpid.apache.org For additional commands, e-mail: users-h...@qpid.apache.org
