JEP 248: Make G1 the Default Garbage Collector

mark.reinhold at mark.reinhold at
Thu Jul 30 18:56:11 UTC 2015

2015/7/30 11:04 -0700, charlie.hunt at
> ...
> On javac, my observation is that it tends to have a very high object
> allocation rate, and the object lifetimes are somewhat short.  And, I
> suppose if we think about what javac does, I suppose we can come to
> terms as to why that’s the case. I imagine if one put forth a
> concerted effort, javac could be improved (probably true for many apps
> too).

If you mean to imply that high allocation rates and short lifetimes are,
necessarily, signs of a poorly-written application then I'll have to
disagree.  Sure, these things can be done to extremes, but I don't think
javac does that and I'd hate to see it re-engineered to "improve" these
particular metrics.  It might be better just to change javac's launcher
to specify the Parallel GC, since this is most definitely an application
for which pause times are irrelevant.

>        Performance of javac is certainly one we want to pay close
> attention due to its impact to the developer use case.

No argument there!

- Mark

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