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
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