[13] RFR(xs) 8226462: [TESTBUG] runtime/appcds/sharedStrings/SysDictCrash.java failed with Cannot dump shared archive

[Calvin Cheung]

Hi David, Ioi,

Here's the latest webrev:
     http://cr.openjdk.java.net/~ccheung/8226462/webrev.02/

I'll push the change after more testing.

thanks,
Calvin

On 6/24/19, 7:19 PM, David Holmes wrote:
> Hi Calvin,
>
> On 24/06/2019 7:10 pm, Calvin Cheung wrote:
>> Hi David,
>>
>> On 6/24/19, 2:59 PM, David Holmes wrote:
>>> Hi Calvin,
>>>
>>> On 23/06/2019 10:50 pm, Calvin Cheung wrote:
>>>> Hi David,
>>>>
>>>> Thanks for your review!
>>>>
>>>> I've a different fix by issuing a warning message from the VM and 
>>>> have the dump time part of the test to look for that warning 
>>>> message in case there's a RuntimeException. If there's such 
>>>> warning, don't continue further.
>>>>
>>>> Here's an updated webrev:
>>>>      http://cr.openjdk.java.net/~ccheung/8226462/webrev.01/
>>>>
>>>> Warning message looks like the following:
>>>>
>>>> Java HotSpot(TM) 64-Bit Server VM warning: UseCompressedOops and 
>>>> UseCompressedClassPointers have been disabled due to max heap 
>>>> 33768409088 > compressed oop heap 32178700288
>>>> Java HotSpot(TM) 64-Bit Server VM warning: Please check the setting 
>>>> of MaxRAMPercentage 12.50
>>>
>>> If a warning is needed I think this should be a single warning, not 
>>> two.
>>>
>>> But I'm concerned that this warning may be triggered unexpectedly in 
>>> some of our test runs and that other tests won't be prepared for 
>>> this warning to appear.
>> How about changing it to a cds log statement?
>>
>> diff --git a/src/hotspot/share/runtime/arguments.cpp 
>> b/src/hotspot/share/runtime/arguments.cpp
>> --- a/src/hotspot/share/runtime/arguments.cpp
>> +++ b/src/hotspot/share/runtime/arguments.cpp
>> @@ -1815,6 +1815,10 @@
>>         // was not specified.
>>         if (reasonable_max > max_coop_heap) {
>>           if (FLAG_IS_ERGO(UseCompressedOops) && override_coop_limit) {
>> +          log_info(cds)("UseCompressedOops and 
>> UseCompressedClassPointers have been disabled due to"
>> +            " max heap " SIZE_FORMAT " > compressed oop heap " 
>> SIZE_FORMAT ". "
>> +            "Please check the setting of MaxRAMPercentage %5.2f."
>> +            ,(size_t)reasonable_max, (size_t)max_coop_heap, 
>> MaxRAMPercentage);
>>             FLAG_SET_ERGO(UseCompressedOops, false);
>>             FLAG_SET_ERGO(UseCompressedClassPointers, false);
>>           } else {
>>
>> An example is:
>> [0.002s][info][cds] UseCompressedOops and UseCompressedClassPointers 
>> have been disabled due to max heap 43082346496 > compressed oop heap 
>> 32178700288. Please check the setting of MaxRAMPercentage 70.00.
>
> Yes that seems better.
>
> Thanks,
> David
>> thanks,
>> Calvin
>>
>>>
>>> David
>>> -----
>>>
>>>> thanks,
>>>> Calvin
>>>>
>>>> On 6/21/19, 6:00 PM, David Holmes wrote:
>>>>> Hi Calvin,
>>>>>
>>>>> On 21/06/2019 3:16 pm, Calvin Cheung wrote:
>>>>>> bug: https://bugs.openjdk.java.net/browse/JDK-8226462
>>>>>>
>>>>>> webrev: http://cr.openjdk.java.net/~ccheung/8226462/webrev.00/
>>>>>>
>>>>>> On a test host with large amount of RAM, the UseCompressedOops 
>>>>>> and the UseCompressedClassPointers flags would be disabled 
>>>>>> ergonomically by the VM with the MaxRAMPercentage set to 12.5. To 
>>>>>> void the test failure, the test has been changed to check the 
>>>>>> given MaxRAMPercentage and uses it if the setting is <= 12.5.
>>>>>
>>>>> But if it fails on 12.5 presently then you would need to be < 12.5 
>>>>> surely?
>>>>>
>>>>> And it's not the 12.5 per-se that is the issue IIUC but the amount 
>>>>> of memory that 12.5% of RAM represents. If there is more memory 
>>>>> you would need to use a smaller % to ensure it works - no?
>>>>>
>>>>> Thanks,
>>>>> David
>>>>> -----
>>>>>
>>>>>> Ran the test 20 times on the linux test host where the failure 
>>>>>> was reproduced.
>>>>>>
>>>>>> thanks,
>>>>>> Calvin