Support gc logs where each gc event is described on a single line

[AlinaHovakimyan]

GCtoolkit does not support simple logs. That is, logs where each GC event is described on a single line. Such log, for example, can be generated, when using Parallel GC with unified logging and minimal arguments.
Example vm args: -XX:+UseParallelGC -Xlog:gc:file=gc.log
Example log: gc_parallel.log

Why this is important:
These minimal-configuration logs sometimes are the first logs users produce when diagnosing GC behavior, before they move on to more advanced logging options.

[karianna]

Hi @AlinaHovakimyan - that is somewhat by design in terms of the scope from the original authors (we typically guide users through the minimal useful settings for GC log analysis). We're not saying that we would never support these simpler logs, but I think we'd be looking for community contributions there and making sure that the end use is aware that they should really be adding a minimal set of flags.

[dsgrieve]

@karianna - this looks like issue #372, or at least the reason why gctoolkit needs more than just default logging.

[AlinaHovakimyan]

Thank you @karianna and @dsgrieve for your reply. Do you know if adding this support will require significant changes ?

[karianna]

Thank you @karianna and @dsgrieve for your reply. Do you know if adding this support will require significant changes ?

I'm not sure, I suspect hte parser work will be fairly minimal, but surfacing the data may be more complex as the domain layers expect richer data.

[jlittle-ptc]

Also #457 is a similar issue which I've submitted a fix for, but is not yet available in release.