Re: [Log4cpp-devel] RE: Log4cpp on OpenVMS

[Bastiaan B. <bas...@li...>]

Tony Cheung wrote:

>Hi Steve and others,
>
>First, the changes (if made) will be applied to OpenVMS compilations
>only. I am not sure if other platforms require the changes.
>
>For the disk caching, in order allow other users to "tail -f" on the
>application log real-time. The OS needs to flush the changes to the disk
>after each line of the logging. The caching should only be applicable to
>within a single line of logging, otherwise there would be a delay for
>the last few lines of logging to show up. BTW, the fsync() returns
>before the I/O completes. 
>
>I agree it's a tradeoff between real-time feedback or better disk
>performance.
>
>Ideas?
>
>Tony
>

This feature may be more generally useful as well. In combination with a 
write cache disabled disk it can provide 'extra safe' logging. Of course 
log4j/log4cpp are still 'non reliable, best effort'  loggers, but this 
may help a bit.
So I  suggest to add this as a runtime option to FileAppender. Now for 
the implementation,  doe anyone have a good opion on whether to use 
fdatasync() or the O_SYNC open flag?
 
Bastiaan