reason for endless backpressure

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reason for endless backpressure

yidan zhao
I've had a problem many times. When the task suddenly continues to back pressure, the back pressure node will no longer send any records unless the task is restarted. But I can confirm that it's not due to high pressure. During the back pressure period, the CPU utilization of the machine is all reduced, but not increased.

At present, I initially suspect that it has something to do with the Internet. Does anyone know the principle? Can network jitter cause this phenomenon?
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Re: reason for endless backpressure

Piotr Nowojski-4
Hi,

If you have an unstable network, which is dropping packets in a weird way (data is lost, but the connection is still kept alive from the perspective of the underlying operating system) it could happen that task will be perpetually blocked. But this is extremely rare. I would first suggest trying to look in other directions. For example if maybe your Task is stuck/deadlocked somewhere in your code? I would suggest attaching a debugger to the problematic TaskManager and/or gather some stack traces. 

If it's indeed a network or hardware issue, a good question would be if it's happening always on the same physical machine? Last time I saw a user reporting a similar problem it ended up being a faulty machine.

Best,
Piotrek



śr., 6 sty 2021 o 17:16 赵一旦 <[hidden email]> napisał(a):
I've had a problem many times. When the task suddenly continues to back pressure, the back pressure node will no longer send any records unless the task is restarted. But I can confirm that it's not due to high pressure. During the back pressure period, the CPU utilization of the machine is all reduced, but not increased.

At present, I initially suspect that it has something to do with the Internet. Does anyone know the principle? Can network jitter cause this phenomenon?