Re: [boost] [asio] Randomly having problems reading from the socket

Subject: Re: [boost] [asio] Randomly having problems reading from the socket
From: Torben Wiggerich (torben.wiggerich_at_[hidden])
Date: 2011-05-09 04:01:50

Am 05.05.2011 16:30, schrieb Cliff Green:
> The symptoms you describe, based on the code you included in your 
> first e-mail, seems to point to a simple and straightforward problem - 
> you're running into TCP flow control blockage. This is a traditional 
> TCP problem and is not directly related to Asio.
>
> Anytime you're sending data as fast as possible, and the receiving 
> side is just slightly slower at receiving the data, send buffers in 
> the OS will fill up. Eventually this will result in the send being 
> blocked for a short period of time while the receiving side processes 
> the data. If you're using blocking writes, the send will block for a 
> period of time. If you're using async writes, the write completion 
> handler will take longer before it is called (which is why I greatly 
> prefer async operations all around).
>
> That the problem is transitory and takes a while to manifest is 
> another clue - it depends totally on how fast the sending and 
> receiving applications are running, and if there's a short period on 
> the receiving side where the app can't run as fast (e.g. another app 
> takes up some processing time), the blockage will be transitory.
>
> Cliff
>

Thanks for your answer and Sorry for my late response...

So I will give the asynchronous connection a try ...

If I understand you correct, just the sender should be blocked for a 
time. You say that it is because the buffers are running full. Is there 
a method to detect if the buffers are full, so that I should stop 
sending new packets? It would be ok if it stops for a few milliseconds, 
but not for a such long time like 5 seconds...
But I also don't understand how both sides can stop receiving and 
sending data for 5 seconds at the same time...

On the other hand the application where I observed this error didn't 
produce so frequently network traffic at all. It produces this packages 
only with 25 Hz...

Kind regards
Torben