ZMQ do not drop messages on sub side when the HWM is reached.
I have a pub process which send 2000 messages as fast as it can. The sub process needs 2 seconds to process each message.
Case 1: No HWM on sub side All messages are transferred to the sub side and stored in its queue (Confirmed by wireshark running on the sub host)
Case 2; HWM = 4 on sub side No messages are dropped even if the sub socket entered its exceptional state (because HWM reached) On Wireshark, we see that after a while, the TCP connnection between the pub and sub is slow down due to TCP window full and TCP ZerWindow packets exchanged between peers. According to the man page, messages should be dropped by the subscriber. This is not the case
ZMQ do not drop messages on sub side when the HWM is reached.
I have a pub process which send 2000 messages as fast as it can.
The sub process needs 2 seconds to process each message.
Case 1: No HWM on sub side
All messages are transferred to the sub side and stored in its queue (Confirmed by wireshark running on the sub
host)
Case 2; HWM = 4 on sub side
No messages are dropped even if the sub socket entered its exceptional state (because HWM reached)
On Wireshark, we see that after a while, the TCP connnection between the pub and sub is slow down due to
TCP window full and TCP ZerWindow packets exchanged between peers.
According to the man page, messages should be dropped by the subscriber. This is not the case
Emmanuel