Hi,
----- Original Message -----
>
>
> Another one from the developerâs meeting.
>
I can't remember all of the context of this one, I think it was Frank
who pointed out -u but the context is eluding me...
>
> The âu option to pmlogger is not really unbuffered. Weâre still using stdio
> and stdio buffers and stdio default buffer flushing, but weâre adding
> fflush() calls in the correct order (meta data file, data file, index file)
> at the end of each logical record written to the archive (after each
> pmFetch).
>
*nod*
>
> This closes, but does not remove the time window in which the physical files
> are not consistent and aligned with the end of a logical archive record.
>
Is our concern about "not consistent" here on-disk or in-memory consistency?
>
> -u can be passed to all the pmloggers being managed by pmlogger_check and
> friends by adding âu to each line in the control file.
>
Not clear who (which tools?/code?) benefit from that, if anyone...?
>
> As I see it, we have 3 options:
> [...]
> Thoughts? Comments?
>
I think we need some demonstrated, concrete, actual issues here - its all a
bit too hypothetical at this stage - a (QA?) tool that attempts to read from
the end of a growing log file for starters, and the clear existence of some
problems, before we start fixing them. Do we have such a QA tool already?
(reading the cases covered in pmGetArchiveEnd in libpcp suggests we might?)
thanks.
--
Nathan
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