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An unexpected perf feature
LWN.net Weekly Edition for May 16, 2013
A look at the PyPy 2.0 release
PostgreSQL 9.3 beta: Federated databases and more
LWN.net Weekly Edition for May 9, 2013
The undocumented format is annoying.
The Journal - a proposed syslog replacement
Posted Nov 18, 2011 18:38 UTC (Fri) by jake (editor, #205)
My sense is that they are trying not to get trapped into backward compatibility games by having other programs that read/write the data without using the supplied library. I don't think they plan to deliberately obfuscate the format (and they will be providing code to both read and write it), but my guess is that they don't want to get stuck into a particular format forevermore because someone wrote a program that grabbed the 12th byte of every record and decided that some data would always appear there.
It's essentially the ABI problem that the kernel runs into, and that sometimes makes it difficult to change things in the kernel (like tracepoints for example).
Posted Nov 18, 2011 18:47 UTC (Fri) by mathstuf (subscriber, #69389)
Posted Nov 18, 2011 21:29 UTC (Fri) by elanthis (guest, #6227)
Once it's a stable feature, expect the format to be documented. Until then, the documentation is available in the .c files for anyone who has some need to avoid the provided library interface.
Posted Nov 18, 2011 21:57 UTC (Fri) by mathstuf (subscriber, #69389)
This is understandable, even appreciated. Having multiple minor versions of varying usefulness indefinitely supported just because they existed for a commit or two during the inital format designs would be crazy to expect.
> Once it's a stable feature, expect the format to be documented.
> At this point we have no intention to standardize the format
We might document the on-disk format eventually
This is not a strong a guarantee as I'd like for this and certainly not something that would range a high level of expectancy from me. Before it becomes default in a major distribution, I'd like to see a format specification.
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