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<== Date ==> <== Thread ==>

Subject: RE: asyn timeout
From: Mark Rivers <rivers@cars.uchicago.edu>
To: "'Eric Norum'" <wenorum@lbl.gov>
Cc: "tech-talk@aps.anl.gov" <tech-talk@aps.anl.gov>
Date: Mon, 19 Oct 2015 16:01:48 +0000

Ø  ASYN already provides a timeout mechanism with the option of tearing down the TCP connection on timeouts.

 

But that requires an additional delay in detecting that the socket has indeed disconnected by waiting for a write or read operation to time out.  And what if the remote end is sending unsolicited messages at some unknown interval?  It would then be up to the remote end to determine that a write failed and tear down the socket and reopen it? Could there be state information lost when a socket is closed and then re-opened?  It seems cleaner to let the underlying OS implementation optionally take care of sending keepalive packets to prevent the types of problems Pedro is seeing?

 

Mark

 

 

From: Eric Norum [mailto:wenorum@lbl.gov]
Sent: Monday, October 19, 2015 10:53 AM
To: Mark Rivers
Cc: Torsten bögershaus; Pedro Gigoux; tech-talk@aps.anl.gov
Subject: Re: asyn timeout

 

What’s use case for SO_KEEPALIVE?  ASYN already provides a timeout mechanism with the option of tearing down the TCP connection on timeouts.

 

On Oct 19, 2015, at 8:46 AM, Mark Rivers <rivers@cars.uchicago.edu> wrote:

 

Should asyn be setting SO_KEEPALIVE by default?  Perhaps drvAsynIPPort should implement the asynOption interface and we could control things like this over that interface, like drvAsynSerialPort does for baud rate, stop bits, etc.?

 

-- 
Eric Norum
wenorum@lbl.gov

 


References:
asyn timeout Pedro Gigoux
Re: asyn timeout Torsten bögershaus
RE: asyn timeout Mark Rivers
Re: asyn timeout Eric Norum

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