[BUG] The minBytes and maxWait parameters in the fetch request are invalid

[lordcheng10]

Describe the bug
When the client consumes a topic with no data, the client will send fetch requests frantically. Under normal circumstances, when the server's data is less than fetchRequest.minBytes(), it should wait until the data arrives or timeout. One impact of this is: when there are too many such clients, server-side cpu resources will be severely consumed, affecting service stability：

Solution
I try to delay response on the KoP server, when the amount of readable data is less than fetchRequest.minBytes()

[BewareMyPower]

You're right, it was not supported yet. I also found the problem of consumer side when I ran performance tests. Since we've already migrated the DelayedOperation, I think it would not be hard to support it. I'm going to process this issue after I finished my current task. Or would you like to contributed a PR to fix it?

[lordcheng10]

You're right, it was not supported yet. I also found the problem of consumer side when I ran performance tests. Since we've already migrated the DelayedOperation, I think it would not be hard to support it. I'm going to process this issue after I finished my current task. Or would you like to contributed a PR to fix it?

I am willing to fix this problem, please assign this issue to me！ @BewareMyPower

[lordcheng10]

You're right, it was not supported yet. I also found the problem of consumer side when I ran performance tests. Since we've already migrated the DelayedOperation, I think it would not be hard to support it. I'm going to process this issue after I finished my current task. Or would you like to contributed a PR to fix it?

@BewareMyPower I have mentioned a PR here #702