RFR: (S): 8142935: Adding old gen regions does not consider available free space

Derek White derek.white at oracle.com
Mon Mar 21 13:54:52 UTC 2016


Hi Tom,

On 3/19/16 9:10 AM, Tom Benson wrote:
> Hi Derek,
> Thanks for taking a look.    I see that the link under the webrev text 
> was bad due to cut/paste, so here's a good one for any new readers:
>   Webrev: http://cr.openjdk.java.net/~tbenson/8142935/webrev/
>
> On 3/18/2016 6:22 PM, Derek White wrote:
>>
>> My main question is that it looks like the accounting:
>>
>>     _inc_bytes_used_before
>>     _inc_bytes_live_before
>>     _bytes_used_before
>>     _bytes_lived_before
>>
>> are a summary of the bytes used and live in the young regions.
>>
>> In the new test in G1CollectionSet::finalize_old_part(), I don't see 
>> that it's accounting for the live bytes of the old regions it already 
>> added to the cset. For example if the young regions had no live data, 
>> then we might still add too many old regions to the cset?
>
> The update to _bytes_live_before at line 100 of g1CollectionSet.cpp is 
> inside add_old_region(), so I think that should account for them.  Thanks,

OK, I see it. I agree with Kim's comment to, otherwise looks great.

  - Derek
> Tom
>
>
>>
>> The rest of it looks good.
>>
>>  - Derek
>

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