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<div class="moz-cite-prefix">Hi Milan,<br>
<br>
I cannot give an authoritative answer to that, but since
Shenandoah is very similar in this respect, and from my experience
with Shenandoah, I think that full GC is not a very high priority.
It is meant as a last-ditch collection, when all else fails to
free enough space. In a good world, with perfect GC heuristics and
well behaving applications, it should never happen, and thus
performance shouldn't matter much.<br>
<br>
However, this world is not ideal, and full GC performance does
matter, especially when you got a large heap, and run into it and
lose *seconds* (or even minutes) on it.<br>
<br>
That being said, we do have a parallel full GC in Shenandoah, and
its performance gets close to, and even sometimes exceeds,
parallel GC. Maybe it's worth to adopt it for G1? It should be
relatively straightforward, because both G1 and Shenandoah are
region based. It does compact objects towards the bottom of the
heap, while mostly retaining their relative order.<br>
<br>
Roman<br>
<br>
Am 27.07.2017 um 10:15 schrieb Milan Mimica:<br>
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<blockquote type="cite"
cite="mid:CAC+6wjpSRTQ3-u3rJ_nnashDZyEQBcOE8rU_zh+WEo7ChzNMJw@mail.gmail.com">
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<div>Hi<br>
<br>
</div>
Can I have just a short explanation why G1 Full GC wasn't
implemented as parallel in the first place, given "the
assumption that nothing in the fundamental design of G1 prevents
a parallel full GC."?<br>
<br>
<br>
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<br>
<div class="gmail_quote">
<div dir="ltr">sri, 26. srp 2017. u 23:11 <<a
href="mailto:mark.reinhold@oracle.com"
moz-do-not-send="true">mark.reinhold@oracle.com</a>>
napisao je:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">New JEP
Candidate: <a href="http://openjdk.java.net/jeps/307"
rel="noreferrer" target="_blank" moz-do-not-send="true">http://openjdk.java.net/jeps/307</a><br>
<br>
- Mark<br>
</blockquote>
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