RFR: 8232588: G1 concurrent System.gc can return early or late

[Thomas Schatzl]

Hi,

On 11.11.19 20:40, Kim Barrett wrote:
>> On Nov 7, 2019, at 4:02 PM, Kim Barrett <kim.barrett at oracle.com> wrote:
>>
>>> On Nov 7, 2019, at 4:58 AM, Thomas Schatzl <thomas.schatzl at oracle.com> wrote:
>>>> New webrevs:
>>>> full: https://cr.openjdk.java.net/~kbarrett/8232588/open.01/
>>>> incr: https://cr.openjdk.java.net/~kbarrett/8232588/open.01.inc/
>>>
>>> Looks good (obviously missing the items discussed here).
> 
> After sending out the open.01* set of webrevs I noticed the comment
> describing should_do_concurrent_full_gc had fallen out of date a while
> ago (should have been updated by JDK-8212657), and could also use a
> bit of tidying up.  I'd like to deal with this now, since it's minimal
> and I'm waiting on a 2nd reviewer.
> 
> Changes are to add missing _g1_periodic_collection to the list and
> regularize punctuation there, and improve wording of the description.
> Not bothering with a webrev for now; here's the diff:
> 
> diff -r f95bdf58fc7e -r a772f9ce0594 src/hotspot/share/gc/g1/g1CollectedHeap.hpp
> --- a/src/hotspot/share/gc/g1/g1CollectedHeap.hpp	Wed Nov 06 18:52:16 2019 -0500
> +++ b/src/hotspot/share/gc/g1/g1CollectedHeap.hpp	Mon Nov 11 14:36:22 2019 -0500
> @@ -256,14 +256,14 @@
>   
>     G1HRPrinter _hr_printer;
>   [...]
> +  // (f) cause == _g1_periodic_collection and +G1PeriodicGCInvokesConcurrent.
>     bool should_do_concurrent_full_gc(GCCause::Cause cause);
>   
>     // Attempt to start a concurrent cycle with the indicated cause.
> 

   still looks good.

Thomas