Updated: RFR(L) 8046598: Scalable Native memory tracking development
Zhengyu Gu
zhengyu.gu at oracle.com
Wed Aug 6 16:45:47 UTC 2014
Thanks, George.
I will fix them accordingly.
-Zhengyu
On 8/6/2014 12:40 PM, George Triantafillou wrote:
> Hi Zhengyu,
>
> I found some typos. Otherwise, it looks good.
>
> -George
>
> src/share/vm/services/memTracker.hpp:
>
> 142 // Launcher only obligates to pass native memory tracking
> 142 // Launcher only obligated to pass native memory tracking
>
> 143 // option value, but not obligates to validate the value,
> 143 // option value, but not obligated to validate the value,
>
> 192 // chuncks that backing up the arena.
> 192 // chunks backing up the arena.
>
> src/share/vm/services/mallocTracker.hpp:
>
> 181 // from total chuncks to get total free chunck size
> 181 // from total chunks to get total free chunk size
>
> src/share/vm/services/virtualMemoryTracker.cpp:
>
> 75 // the two adjacent regions have to same call stack, merge them
> 75 // the two adjacent regions have the same call stack,
> merge them
>
> 314 // Overalpped reservation.
> 314 // Overlapped reservation.
>
> src/share/vm/utilities/linkedlist.hpp:
>
> 37 // as the linked list what contains this entry.
> 37 // as the linked list that contains this entry.
>
> 57 // any storage type it uses, so all methods involves
> 57 // any storage type it uses, so all methods involving
>
> src/share/vm/services/mallocSiteTable.hpp:
>
> 73 // The operation can be failed due to contention from other
> thread.
> 73 // The operation can fail due to contention from another thread.
>
> src/share/vm/services/mallocSiteTable.cpp:
>
> 173 // contented, other thread won
> 173 // contended, other thread won
>
>
> On 8/4/2014 2:22 PM, Zhengyu Gu wrote:
>> The update is based on code review meetings with Coleen, Christian,
>> George and Harold.
>>
>> http://cr.openjdk.java.net/~zgu/8046598/webrev.01/
>> <http://cr.openjdk.java.net/%7Ezgu/8046598/webrev.01/>
>>
>>
>> Thanks,
>>
>> -Zhengyu
>>
>>
>>
>> On 7/15/2014 4:12 PM, Zhengyu Gu wrote:
>>> This is an update to previous RFR 8028541: Native Memory Tracking
>>> enhancement, the original one is closed as duplicate of current one.
>>>
>>> The update is mainly based on feedback from Coleen and Christian:
>>> - Refactored MemReporter to break up some large functions and
>>> eliminate duplicated code.
>>> - Minor change to MemBaseline for eliminating duplicated code.
>>> - Changed MEMFLAGS type from unsigned short => MemoryType.
>>>
>>> Also added unit tests for LinkedList.
>>>
>>> The note from RFR 8028541:
>>> =========================
>>> This is significant rework of native memory tracking introduced in
>>> earlier releases.
>>>
>>> The goal of this enhancement is to improve scalability, from both
>>> tracking memory and CPU usage perspectives, so it can scale well
>>> with increased memory allocation in large applications.
>>>
>>> The enhancement is mainly focused on malloc memory tracking, whose
>>> activities are several magnitude higher than virtual memory, and was
>>> the main bottleneck in early implementation.
>>>
>>> Instead of using book keeping records for tracking malloc
>>> activities, new implementation co-locates tracking data along side
>>> with user data by using a prefixed header. The header size is 8
>>> bytes on 32-bit systems and 16 bytes on 64-bit systems, which ensure
>>> that user data also align properly.
>>>
>>> Virtual memory tracking still uses book keeping records, and
>>> ThreadCritical lock is always acquired to alter the records and
>>> related data structures.
>>>
>>> Summary tracking data is maintained in static data structures, via
>>> atomic operations. Malloc detail tracking call stacks are maintained
>>> in a lock free hashtable.
>>>
>>> The key improvements:
>>> 1. Up-to-date tracking report.
>>> 2. Detail tracking now shows multiple call frames. Number of
>>> frames is compilation time decision, currently default to 4.
>>> 3. Malloc tracking is lock free.
>>> 4. Tracking summary is reported in hs_err file when native memory
>>> tracking is enabled.
>>> 5. Query is faster, uses little memory and need a very little
>>> process.
>>>
>>> The drawback is that, malloc tracking header is always needed if
>>> native memory tracking has ever been enabled, even after tracking is
>>> shutdown.
>>>
>>> Impacts:
>>> The most noticeable impact for JVM developers, is that Arena now
>>> also take memory type as constructor parameter, besides the new
>>> operators.
>>> Arena* a = new (mtCode) Arena() => Arena* a = new (mtCode)
>>> Arena(mtCode)
>>>
>>> The webrev shows modification of about 60 files, but most of them
>>> are due to tracking API changes, mainly due to tracking stack, now,
>>> is an object, vs. a single pc.
>>>
>>> The most important files for this implementations are:
>>>
>>> memTracker.hpp/cpp
>>> mallocTracker.hpp/cpp and mallocTracker.inline.hpp
>>> virtualMemoryTracker.hpp/cpp
>>> mallocSiteTable.hpp/cpp
>>>
>>> allocationSite.hpp
>>> nativeCallStack.hpp/cpp
>>> linkedlist.hpp
>>>
>>>
>>> Tests:
>>> - JPRT
>>> - NMT test suite
>>> - vm.quick.testlist
>>> - Kitchensink stability test for 16+ days
>>> - FMW
>>>
>>>
>>>
>>>
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8046598
>>> Webrev: http://cr.openjdk.java.net/~zgu/8046598/webrev.00/
>>> <http://cr.openjdk.java.net/%7Ezgu/8046598/webrev.00/>
>>>
>>>
>>>
>>> Thanks,
>>>
>>> -Zhengyu
>>>
>>
>
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