[zeromq-dev] Maximum message size on Windows

[Pieter Hintjens]

Ah, you can of course break larger messages into any number of frames... :)
On Aug 21, 2013 2:47 PM, "Merijn Verstraaten" <merijn at inconsistent.nl>
wrote:

> Well, considering the wire protocol is limited to long sizes of 64bit
> unsigned, I guess it would be appropriate to consider 2^64 - 1 bytes the
> maximum message size. Which is almost the same as "no limit" given current
> hardware circumstances, I guess.
>
> Cheers,
> Merijn
>
> On Aug 21, 2013, at 12:05 , Alan Ward wrote:
> > Hi Pieter,
> > Thanks for the quick response.
> >
> > Alan
> >
> > -----Original Message-----
> > From: zeromq-dev-bounces at lists.zeromq.org
> > [mailto:zeromq-dev-bounces at lists.zeromq.org] On Behalf Of Pieter
> Hintjens
> > Sent: 21 August 2013 11:52
> > To: ZeroMQ development list
> > Subject: Re: [zeromq-dev] Maximum message size on Windows
> >
> > There is no maximum defined message size. What you are seeing is the
> default
> > stack size of 1MB being hit by your use of a huge local variable.
> >
> > In general do not put anything larger than a few kilobytes into local
> > storage since depending on the build, the stack can be as small as 4KB.
> You
> > don't get any warning, just a nasty crash.
> >
> > Use dynamic allocation, and it will work up to the limit of heap memory.
> >
> > -Pieter
> >
> > On Wed, Aug 21, 2013 at 12:43 PM, Alan Ward <alan.ward at btinternet.com>
> > wrote:
> >> Hi,
> >> I have an application that I have been developing on Linux (Ubuntu)
> >> for a few months.
> >> I am now trying to port it to Windows.
> >>
> >> After battling with Visual Studio for a while I now have the code
> >> executing, but have immediately hit a problem with the maximum message
> > size.
> >>
> >> On Linux I have a maximum message size of 1Mb (1048576). This is
> >> fairly arbitrary so I can reduce it.
> >> On Windows this causes zmq_recv to crash. I have found that the
> >> threshold is around 1027830.
> >>
> >> I am using the 32-bit version of zeromq (3.2.3) on Windows and 64-bit
> >> (3.2.2) on Linux.
> >>
> >> The following code snippet causes an exception on my system.
> >>
> >> #include <zmq.h>
> >> #include <stdio.h>
> >> #include <tchar.h>
> >> #include <string.h>
> >> #include <assert.h>
> >>
> >> int _tmain(int argc, _TCHAR* argv[])
> >> {
> >>    int rc;
> >>    char buffer [ 1027830 ];
> >>    void *context;
> >>    void *responder;
> >>    size_t msg_size;
> >>
> >>    puts("start");
> >>    context = zmq_ctx_new ();
> >>    responder = zmq_socket (context, ZMQ_REP);
> >>    rc = zmq_bind (responder, "tcp://*:5555");
> >>    if ( rc != 0 ) { printf("zmq_bind error: rc:%d:errno:%d\n", rc,
> >> errno); return 1; }
> >>
> >>    msg_size = zmq_recv (responder, buffer, 2048, 0);
> >>
> >>    return 0;
> >> }
> >>
> >> Is there a defined maximum size? I did search for some information on
> >> this a while ago, but found nothing.
> >>
> >> Regards,
> >> Alan
> >>
> >> _______________________________________________
> >> zeromq-dev mailing list
> >> zeromq-dev at lists.zeromq.org
> >> http://lists.zeromq.org/mailman/listinfo/zeromq-dev
> > _______________________________________________
> > zeromq-dev mailing list
> > zeromq-dev at lists.zeromq.org
> > http://lists.zeromq.org/mailman/listinfo/zeromq-dev
> >
> >
> > -----
> > No virus found in this message.
> > Checked by AVG - www.avg.com
> > Version: 2013.0.3392 / Virus Database: 3211/6594 - Release Date: 08/20/13
> >
> > _______________________________________________
> > zeromq-dev mailing list
> > zeromq-dev at lists.zeromq.org
> > http://lists.zeromq.org/mailman/listinfo/zeromq-dev
>
>
> _______________________________________________
> zeromq-dev mailing list
> zeromq-dev at lists.zeromq.org
> http://lists.zeromq.org/mailman/listinfo/zeromq-dev
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.zeromq.org/pipermail/zeromq-dev/attachments/20130821/8d572ff6/attachment.htm>