[K/N] Recursive timing issue with GC Scheduler MutatorAssists when destroying millions of meta objects

[edisongz]

MoveAndAdvance moved objects were incorrectly counted as freed,
causing totalAllocatedBytes >= targetHeapBytes to persist longer than
necessary. This led to unnecessary GC recursion and degraded performance
in -Xallocator=std mode.

^KT-76851

[projedi]

Thanks! I have some preliminary questions, let's discuss them in the ticket: https://youtrack.jetbrains.com/issue/KT-76851/Kotlin-Native-GC-scheduler-MutatorAssists-requestAssists-and-completeEpoch-issue#focus=Comments-27-12001003.0-0 ?

[dkhalanskyjb]

Asking the whole JetBrains/kotlin for a review is a bit excessive.

[edisongz]

Asking the whole JetBrains/kotlin for a review is a bit excessive.

So sorry for that, I just submitted a new commit, which automatically triggered a review request.
I have no right to edit reviewers, it's very embarrassing.

[SmialyKot]

Hey, GitHub CODEOWNERS is a new addition for the project and we're still working out the kinks. The team JetBrains/kotlin was automatically selected for review since it's assigned to *Generated.java files - I will make sure to disable notifications for the review teams

EDIT: All review teams have notifications disabled. Anyone who receives unwanted notifications should verify "Watch" settings on the main page of the repository:

[projedi]

@edisongz it seems, runtime tests are failing.

[tid#245982] gc/common/cpp/GCStatistics.cpp:222: runtime assert: Mismatch in statistics: marked 0 objects, while 2 are alive after sweep
0   linux_x64CmsGcTest.kexe             0x2d9167           _ZN12_GLOBAL__N_111PrintAssertEbPKcS1_P13__va_list_tag + 279
1   linux_x64CmsGcTest.kexe             0x2d902d           _ZN6kotlin8internal24RuntimeAssertFailedPanicEbPKcS2_z + 125
2   linux_x64CmsGcTest.kexe             0x2dd883           _ZN6kotlin2gc8GCHandle8finishedEv + 227
3   linux_x64CmsGcTest.kexe             0x2dbeab           _ZN6kotlin2gc8internal8GCThread13PerformFullGCEl + 347
4   linux_x64CmsGcTest.kexe             0x2db93a           _ZN6kotlin13UtilityThread3RunIZNS_2gc8internal8GCThreadC1ER13GCStateHolderRNS2_4mark14ConcurrentMarkERNS_5alloc9AllocatorERNS_11gcScheduler11GCSchedulerEE3$_0JEEENSt13invoke_resultIT_JDpT0_EE4typeEOSI_DpOSJ_ + 90
5   linux_x64CmsGcTest.kexe             0x2dba8d           _ZNSt6thread11_State_implINS_8_InvokerISt5tupleIJPFvN6kotlin12ScopedThread10attributesEOPFvOZNS3_2gc8internal8GCThreadC1ER13GCStateHolderRNS6_4mark14ConcurrentMarkERNS3_5alloc9AllocatorERNS3_11gcScheduler11GCSchedulerEE3$_0ESL_ES5_SN_SK_EEEEE6_M_runEv + 109
6   linux_x64CmsGcTest.kexe             0x3c506d           execute_native_thread_routine + 11
7   libpthread.so.0                     0x7f4b804cd608     0x0 + 139962251793928
8   libc.so.6                           0x7f4b803d7352     clone + 66

Can't tell which exact test is failing, but it looks like the entire suite crashing with an assertion triggered on a GC thread.

You can run all the runtime tests with ./gradlew :kotlin-native:runtime:hostRuntimeTests. Could you please take a look?

[edisongz]

Can't tell which exact test is failing, but it looks like the entire suite crashing with an assertion triggered on a GC thread.

@projedi In std allocator mode, markedCount_ also needs to be accounted. objects to be finalized are kept alive also need record.
After adding the line sweepHandle.addMarkedObject();, all test cases have passed.