Code review request: 7188594 Print statistic collected by NMT with VM flag

[Vladimir Kozlov]

On 8/30/12 5:12 AM, Zhengyu Gu wrote:
> On 8/29/2012 10:34 PM, Vladimir Kozlov wrote:
>> On 8/29/12 6:07 PM, Zhengyu Gu wrote:
>>>
>>>
>>> On 8/29/2012 4:34 PM, Vladimir Kozlov wrote:
>>>> You need to duplicate code in java.cpp in #else version of print_statistics() since you can collect this date in
>>>> product VM. And move warning message to arguments.cpp (and switch off flag if NMT is off):
>>>> if (!MemTracker::is_on() && PrintNMTStatistics) {
>>>> warning(err_msg("Native memory tracking is off due to ", MemTracker::reason()));
>>>> PrintNMTStatistics = false;
>>>> }
>>> NMT can be shutdown during VM execution, through jcmd or by NMT runtime itself in some extreme scenarios, such as
>>> running out of native memory, etc. so the checking in argument parsing phase is not sufficient.
>>
>> Do NMT throw out already collected data (free memory used by data) if it is shutdown this way? If a data still there
>> you can print it even when NMT is off when VM exit.
> It does throw out all data and free memory it used.

OK. In this case I agree that the check in java.cpp is needed. But you also need the check in arguments.cpp.

Vladimir

>
> -Zhengyu
>
>
>>
>> Vladimir
>>
>>>
>>> -Zhengyu
>>>
>>>>
>>>> Vladimir
>>>>
>>>> Vladimir Kozlov wrote:
>>>>> Hi, Zhengyu
>>>>>
>>>>> Could you give an example of output? I thought you need more changes for this.
>>>>>
>>>>> thanks,
>>>>> Vladimir
>>>>>
>>>>> Zhengyu Gu wrote:
>>>>>> This is a simple RFE, that allows VM to dump collected native memory
>>>>>>
>>>>>> tracking data before exits.
>>>>>>
>>>>>> CR: http://bugs.sun.com/view_bug.do?bug_id=7188594
>>>>>> Webrev: http://cr.openjdk.java.net/~zgu/7188594/webrev.00/
>>>>>>
>>>>>> Thanks,
>>>>>>
>>>>>> -Zhengyu
>>>>>>