While allowing 64 byte messages would be faster for messages from size 30-64 am I right in saying it would also incur a penalty for all messages of size greater than 64 bytes ? Since the 64 byte data would be allocated and at the least would incur a memory penalty. Also I suspect the transport affects the results eg for Core2 up to 128 bytes copying was faster for inproc
Ben >-----Original Message----- >From: [email protected] [mailto:zeromq-dev- >[email protected]] On Behalf Of Matt Weinstein >Sent: Sunday, July 25, 2010 1:36 AM >To: 0MQ development list >Subject: Re: [zeromq-dev] Very Small Messages/Manual > >Perhaps there should be a section entitled e.g. " Optimizing ZMQ " >somewhere in the online documentation... > >For example, you *could* tweak the VSM size (according to zmq.h) for >certain applications and architectures -- > >/* Maximal size of "Very Small Message". VSMs are passed by >value */ >/* to avoid excessive memory allocation/ >deallocation. */ >/* If VMSs larger than 255 bytes are required, type of >'vsm_size' */ >/* field in zmq_msg_t structure should be modified >accordingly. */ >#define ZMQ_MAX_VSM_SIZE 30 > >On Jul 24, 2010, at 10:57 AM, Martin Sustrik wrote: > >> Oliver Smith wrote: >>> Martin Sustrik wrote: >>>> Messages below 30 bytes of >>>> length are called VSMs (very small messages) in 0MQ and are passed >>>> *without* any extra memory allocations. >>> Actually, this is a fairly important/useful piece of information. >>> Can I >>> suggest that it be added to the main zmq.html of the manual under the >>> Messages heading? >> >> Hm. It's kind of an implementation detail. Our tests have shown that >> for >> messages below 30 bytes copying them is less expensive than >> allocating/deallocating a chunk for the data. As everything stays >> opaque >> for the users, I am not sure why they would be interested in that kind >> of detail. >> >> Martin >> _______________________________________________ >> zeromq-dev mailing list >> [email protected] >> http://lists.zeromq.org/mailman/listinfo/zeromq-dev > >_______________________________________________ >zeromq-dev mailing list >[email protected] >http://lists.zeromq.org/mailman/listinfo/zeromq-dev _______________________________________________ zeromq-dev mailing list [email protected] http://lists.zeromq.org/mailman/listinfo/zeromq-dev
