[zeromq-dev] Publishers stops sending data after sometime. Subscriber is required to fix publisher

[Justin Karneges]

You'd still have to wait for the TCP keepalive to timeout the
connection before it will recover. On Ubuntu this might be a very long
time, so be sure to set all the ZMQ_TCP_KEEPALIVE_* options to ensure a
shorter timeout.
On Sat, Jan 27, 2018, at 2:27 AM, Ravi Joshi via zeromq-dev wrote:
> Hi Justin,
> 
> I will check it using netstat.
> 
> Meanwhile, ZMQ_TCP_KEEPALIVE seems not working. I still see that after
> some time, Windows OS, where publishers are running, is showing 0 MBPS
> transmission rate. After I restart subscribers in ROS on Ubuntu,
> publishers start working. Please note that during this process I am
> not restarting publishers at all.> 
> Below is the code snippet added to all subscribers-
> 
> int tcp_keepalive = 1;
> 
> zmq_socket.setsockopt(ZMQ_TCP_KEEPALIVE, &tcp_keepalive,
> sizeof(tcp_keepalive));> 
> 
>  -
> Thanks
> Ravi
> 
> 
> On Saturday, 27 January 2018 5:36 PM, Justin Karneges
> <justin at karneges.com> wrote:> 
> 
> One thing you might do is run netstat on both sides to see if the
> connections are still listed. In a dead connection scenario, netstat
> should no longer list the connection on the PUB side, but should
> remain listing it on the SUB side.> 
> Note that it can take time for the PUB connection to give up. On
> Linux, the default is something like 20 minutes after it dies, so give
> the PUB side some extra time after messages stop transmitting. If
> transmission hasn't worked for over 20 minutes and netstat is still
> showing the connection on the PUB side, then the problem may be
> something else.> 
> On Sat, Jan 27, 2018, at 12:13 AM, Ravi Joshi via zeromq-dev wrote:
>> Hi Justin,
>> 
>> Thank you very much. How do I make sure that I am getting dead
>> connections?>> 
>> For time being, I am enabling ZMQ_TCP_KEEPALIVE on all 3 SUB sockets.>> 
>> I will tell you the status of it after sometime.
>> 
>> Thanks
>> -
>> Ravi
>> Sent from Yahoo Mail for iPhone[1]
>> 
>> On Saturday, January 27, 2018, 3:27 PM, Justin Karneges
>> <justin at karneges.com> wrote:>>> Hi,
>>> 
>>> One issue with socket types that don't usually write data (such as
>>> SUB) is that a dead connection might go unnoticed forever. You can
>>> work around this by enabling TCP keep alives on the SUB socket. I
>>> don't know if you're getting dead connections here but just thought
>>> I'd mention it.>>> 
>>> Justin
>>> 
>>> On Fri, Jan 26, 2018, at 9:33 PM, Ravi Joshi via zeromq-dev wrote:
>>> > Hi,
>>> > 
>>> > I am using Publisher-Subscriber pattern consisting of 3
>>> > publishers to>>> > publish 3 different types of data. All 3 publishers are written
>>> > in a>>> > single C# file. However, each subscriber is written in a
>>> > separate C++>>> > file inside ROS. From the point of ZeroMQ, there is no
>>> > difference in>>> > each subscriber, since context, socket initialization and
>>> > receiving>>> > message is done in the same way for all subscriber. Hence, in
>>> > order to>>> > make the mail shorter, I am just posting code snippet of 1 
>>> > subscriber below.
>>> > 
>>> > The publisher code in C# snippet is available in Pastebin 
>>> > (https://pastebin.com/S65LmwuV).
>>> > The subscriber code in C++ snippet is available in Pastebin 
>>> > (https://pastebin.com/xb3V0n0u).
>>> > 
>>> > The publisher works well initially for some time and successfully>>> > transmits data at 700MBPS rate but stops transmitting any data
>>> > after 5-6>>> > hours.
>>> > 
>>> > In order to make publisher working again, I need to restart the 
>>> > subscribers. This is strange to me since it is unexpected
>>> > behavior as>>> > per the Publisher-Subscriber pattern is concerned.
>>> > 
>>> > Why such weird behavior? Any workaround, please.
>>> > 
>>> > -
>>> > Thanks
>>> > Ravi
>>> > _______________________________________________
>>> > zeromq-dev mailing list
>>> > zeromq-dev at lists.zeromq.org
>>> > https://lists.zeromq.org/mailman/listinfo/zeromq-dev
>>> 
>>> _______________________________________________
>>> zeromq-dev mailing list
>>> zeromq-dev at lists.zeromq.org
>>> https://lists.zeromq.org/mailman/listinfo/zeromq-dev
>>>> 
>> _________________________________________________
>> zeromq-dev mailing list
>> zeromq-dev at lists.zeromq.org
>> https://lists.zeromq.org/mailman/listinfo/zeromq-dev
> 
> _______________________________________________
> zeromq-dev mailing list
> zeromq-dev at lists.zeromq.org
> https://lists.zeromq.org/mailman/listinfo/zeromq-dev
> 
> _________________________________________________
> zeromq-dev mailing list
> zeromq-dev at lists.zeromq.org
> https://lists.zeromq.org/mailman/listinfo/zeromq-dev


Links:

  1. https://overview.mail.yahoo.com/?.src=iOS
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.zeromq.org/pipermail/zeromq-dev/attachments/20180127/822bf7c2/attachment.htm>