> This change fixes a long standing performance issue related to the debugger > single stepping that is using JVMTI `FramePop` events as a part of step over > handling. The performance issue is that the target thread continues its > execution in very slow `interp-only` mode in a context of frame marked for > `FramePop` notification with the JVMTI `NotifyFramePop`. It includes other > method calls recursively upon a return from the frame. > > This fix is to avoid enforcing the `interp-only` execution mode for threads > when `FramePop` events are enabled with the JVMTI > `SetEventNotificationMode()`. Instead, the target frame has been deoptimized > and kept interpreted by disabling `OSR` optimization by the function > `InterpreterRuntime::frequency_counter_overflow_inner()`. (Big thanks to > @fisk for this suggestion!) Additionally, some tweaks are applied in several > places where the `java_thread->is_interp_only_mode()` is checked. > The other details will be provided in the first PR request comment. > > Testing: > - test `serviceability/jvmti/vthread/ThreadStateTest` was updated to provide > some extra test coverage > - submitted mach5 tiers 1-6
Serguei Spitsyn has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains nine commits: - merge: fix merge error - Merge - Merge - review: optimize hide_single_stepping and post_method_exit - review: renamed two functions; FRAME_POP_BIT removed from INTERP_EVENT_BITS - review: fix iteration order in process_vthread_pending_deopts as it uses remove_at(idx) - review: fix typo in a EATests.java comment - cleanup: removed an old code fragment in frame.cpp - 6960970: Debugger very slow during stepping ------------- Changes: https://git.openjdk.org/jdk/pull/28407/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28407&range=07 Stats: 255 lines in 22 files changed: 158 ins; 61 del; 36 mod Patch: https://git.openjdk.org/jdk/pull/28407.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/28407/head:pull/28407 PR: https://git.openjdk.org/jdk/pull/28407
