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Subject: Re: R3.14.8 Status/logClient patch
From: Benjamin Franksen <[email protected]>
To: [email protected]
Date: Thu, 17 Nov 2005 01:06:30 +0100
On Wednesday 16 November 2005 21:56, Jeff Hill wrote:
> I did think of one issue. This is using non blocking IO after the
> connect completes. It appears that a delta is that the logRestart
> thread is now doing the periodic flush for *multiple* logging
> circuits. Therefore, if one of the log circuits isnt flowing for
> whatever reason (disk full, marginal circuit, server system power
> off, etc), then all of the other log circuits will not be flushed
> untill logClientSend is called and the specified message will not fit
> (the buffers capacity is exceeded). Since the internal IP kernel
> timeouts for circuit disconnect can be quite long this might prove to
> be problematic.

Hi Jeff,

the simplest way out is to use multiple restart/flush threads, one for 
each log client. It appears that this has the side-advantage of 
somewhat simplifying the code since global variables are no longer 
needed.

Caveat: I don't know what applications (beside the standard ioc log) use 
the logClient facility. If there exist applications that create a lot 
of such clients this would unduly increase IOC load. I don't believe 
that this is the case, though, it doesn't make much sense. At the 
moment I am aware of only one custom application that will use the 
feature at all, namely caPutLog, although others are conceivable.

Ben

PS: One could also use non-blocking send and multiplex clients with a 
select call. This would probably be more complex and also harder to do 
in a portable manner, thorough testing on different platforms etc. No 
way to get this into R3.14.8.

Replies:
RE: R3.14.8 Status/logClient patch Jeff Hill
References:
RE: R3.14.8 Status/logClient patch Jeff Hill

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