Re: Patch review for logging hooks (CF 2012-01)

On 01/18/2012 11:12 AM, Martin Pihlak wrote:
> On 01/18/2012 03:56 AM, Fujii Masao wrote:
>> or syslog process (if you use syslog). So ISTM that there is no
>> guarantee that the order of log messages processed by the
>> hook is same as that of messages written to the log file. For
>> example, imagine the case where two backends call EmitErrorReport()
>> at the same time. Is this OK? If not, the hook might need to be
>> in syslogger.
> For high volume logging I'd avoid going through the syslogger. One
> big issue with syslogger is that it creates a choke point - everything
> has to pass through it, and if it cannot keep up it starts stalling
> the backends. Also, in EmitErrorReport the hook gets to have access
> to the actual ErrorData structure -- that makes filtering and looking
> at message content much simpler.
>
>

Hmm, interesting. I don't think I've encountered a situation where 
backends would actually stall. But in any case, I don't think we have to 
be that deterministic. The only thing that needs to be absolutely 
guaranteed is that the log messages from a given backend are in order. 
Some slight fuzz between backends seems acceptable.

cheers

andrew