RFR: JDK-8175312: SA: clhsdb: Provide an improved heap summary for 'universe' for G1GC

[Jini George]

Thank you very much, Stefan. Could one more reviewer please take a look 
at it ?

- Jini.

On 3/12/2018 8:52 PM, Stefan Johansson wrote:
> Hi Jini,
> 
> This looks good. I'm totally fine with skipping metaspace if that isn't 
> displayed for the other GCs.
> 
> Cheers,
> Stefan
> 
> On 2018-03-09 10:29, Jini George wrote:
>> Here is the revised webrev:
>>
>> http://cr.openjdk.java.net/~jgeorge/8175312/webrev.02/
>>
>> I have made modifications to have the 'universe' command display 
>> details like:
>>
>> hsdb> universe
>> Heap Parameters:
>> garbage-first heap [0x0000000725200000, 0x00000007c0000000] region 
>> size 1024K
>> G1 Heap:
>>    regions  = 2478
>>    capacity = 2598371328 (2478.0MB)
>>    used     = 5242880 (5.0MB)
>>    free     = 2593128448 (2473.0MB)
>>    0.20177562550443906% used
>> G1 Young Generation:
>> Eden Space:
>>    regions  = 5
>>    capacity = 8388608 (8.0MB)
>>    used     = 5242880 (5.0MB)
>>    free     = 3145728 (3.0MB)
>>    62.5% used
>> Survivor Space:
>>    regions  = 0
>>    capacity = 0 (0.0MB)
>>    used     = 0 (0.0MB)
>>    free     = 0 (0.0MB)
>>    0.0% used
>> G1 Old Generation:
>>    regions  = 0
>>    capacity = 155189248 (148.0MB)
>>    used     = 0 (0.0MB)
>>    free     = 155189248 (148.0MB)
>>    0.0% used
>>
>>
>> I did not add the metaspace details since that did not seem to be in 
>> line with the 'universe' output for other GCs. I have added a new 
>> command "g1regiondetails" to display the region details, and have 
>> modified the tests accordingly.
>>
>> hsdb> g1regiondetails
>> Region Details:
>> Region: 0x0000000725200000,0x0000000725200000,0x0000000725300000:Free
>> Region: 0x0000000725300000,0x0000000725300000,0x0000000725400000:Free
>> Region: 0x0000000725400000,0x0000000725400000,0x0000000725500000:Free
>> Region: 0x0000000725500000,0x0000000725500000,0x0000000725600000:Free
>> Region: 0x0000000725600000,0x0000000725600000,0x0000000725700000:Free
>> Region: 0x0000000725700000,0x0000000725700000,0x0000000725800000:Free
>> ...
>>
>> Thanks,
>> Jini.
>>
>>
>> On 2/28/2018 12:56 PM, Jini George wrote:
>>> Thank you very much, Stefan. My answers inline.
>>>
>>> On 2/27/2018 3:30 PM, Stefan Johansson wrote:
>>>> Hi Jini,
>>>
>>>>>> JIRA ID:https://bugs.openjdk.java.net/browse/JDK-8175312
>>>>>> Webrev: 
>>>>>> http://cr.openjdk.java.net/~jgeorge/8175312/webrev.00/index.html
>>>>>>
>>>> It looks like a file is missing, did you forget to add it to the 
>>>> changeset?
>>>
>>> Indeed, I had missed that! I added the missing file in the following 
>>> webrev:
>>>
>>> http://cr.openjdk.java.net/~jgeorge/8175312/webrev.01/
>>>
>>>> ---
>>>> open/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/g1/G1CollectedHeap.java:36: 
>>>> error: cannot find symbol
>>>> import sun.jvm.hotspot.gc.shared.PrintRegionClosure;
>>>> ---
>>>>
>>>> Otherwise the change looks good, but I would like to see the output 
>>>> live. For a big heap this will print a lot of data, just wondering 
>>>> if the universe command is the correct choice for this kind of 
>>>> output. I like having the possibility to print all regions, so I 
>>>> want the change but maybe it should be a different command and 
>>>> 'universe' just prints a little more than before. Something like our 
>>>> logging heap-summary at shutdown:
>>>> garbage-first heap   total 16384K, used 3072K [0x00000000ff000000, 
>>>> 0x0000000100000000)
>>>>   region size 1024K, 4 young (4096K), 0 survivors (0K)
>>>> Metaspace       used 6731K, capacity 6825K, committed 7040K, 
>>>> reserved 1056768K
>>>>   class space    used 559K, capacity 594K, committed 640K, reserved 
>>>> 1048576K
>>>
>>> Ok, will add this, and could probably have the region details 
>>> displayed under a new command called "g1regiondetails", or some such, 
>>> and send out a new webrev.
>>>
>>> Thanks,
>>> Jini.
>>>
>>>>
>>>> Thanks,
>>>> Stefan
>>>>>> Modifications have been made to display the regions like:
>>>>>>
>>>>>> ...
>>>>>> Region: 0x00000005c5400000,0x00000005c5600000,0x00000005c5600000:Old
>>>>>> Region: 0x00000005c5600000,0x00000005c5800000,0x00000005c5800000:Old
>>>>>> Region: 0x00000005c5800000,0x00000005c5a00000,0x00000005c5a00000:Old
>>>>>> Region: 0x00000005c5a00000,0x00000005c5c00000,0x00000005c5c00000:Old
>>>>>> Region: 0x00000005c5c00000,0x00000005c5c00000,0x00000005c5e00000:Free
>>>>>> Region: 0x00000005c5e00000,0x00000005c5e00000,0x00000005c6000000:Free
>>>>>> Region: 0x00000005c6000000,0x00000005c6200000,0x00000005c6200000:Old
>>>>>> ...
>>>>>>
>>>>>> The jtreg test at this point does not include any testing for the 
>>>>>> display of archived or pinned regions. The testing for this will 
>>>>>> be added once JDK-8174994 is resolved.
>>>>>>
>>>>>> The SA tests pass with jprt and Mach5.
>>>>>>
>>>>>> Thanks,
>>>>>> Jini.
>>>>
>