CHANGELOG.md

Changelog

[3.0] - 2024-01-20

Features

• #724: Binary launcher asprof
• #751: Profile non-Java processes
• #795: AsyncGetCallTrace replacement
• #719: Classify execution samples into categories in JFR converter
• #855: ctimer mode for accurate profiling without perf_events
• #740: Profile CPU + Wall clock together
• #736: Show targets of vtable/itable calls
• #777: Show JIT compilation task
• #644: RISC-V port
• #770: LoongArch64 port

Improvements

• #733: Make the same libasyncProfiler work with both glibc and musl
• #734: Support raw PMU event descriptors
• #759: Configure alternative profiling signal
• #761: Parse dynamic linking structures
• #723: --clock option to select JFR timestamp source
• #750: --jfrsync may specify a list of JFR events
• #849: Parse concatenated multi-chunk JFRs
• #833: Time-to-safepoint JFR event
• #832: Normalize names of hidden classes / lambdas
• #864: Reduce size of HTML Flame Graph
• #783: Shutdown asprof gracefully on SIGTERM
• Better demangling of C++ and Rust symbols
• DWARF unwinding for ARM64
• JfrReader can parse in-memory buffer
• Support custom events in JfrReader
• An option to read JFR file by chunks
• Record GCHeapSummary events in JFR

Bug fixes

• Workaround macOS crashes in SafeFetch
• Fixed attach to OpenJ9 on macOS
• Support UseCompressedObjectHeaders aka Lilliput
• Fixed allocation profiling on JDK 20.0.x
• Fixed context-switches profiling
• Prefer ObjectSampler to TLAB hooks for allocation profiling
• Improved accuracy of ObjectSampler in --total mode
• Make Flame Graph status line and search results always visible
• loop and timeout options did not work in some modes
• Restart interrupted poll/epoll_wait syscalls
• Fixed stack unwinding issues on ARM64
• Workaround for stale jmethodIDs
• Calculate ELF base address correctly
• Do not dump redundant threads in a JFR chunk
• check action prints result to a file
• Annotate JFR unit types with @ContentType

[2.9] - 2022-11-27

Features

• Java Heap leak profiler
• meminfo command to print profiler's memory usage
• Profiler API with embedded agent as a Maven artifact

Improvements

• --include/--exclude options in the FlameGraph converter
• --simple and --dot options in jfr2flame converter
• An option for agressive recovery of [unknown_Java] stack traces
• Do not truncate signatures in collapsed format
• Display inlined frames under a runtime stub

Bug fixes

• Profiler did not work with Homebrew JDK
• Fixed allocation profiling on Zing
• Various jfrsync fixes
• Symbol parsing fixes
• Attaching to a container on Linux 3.x could fail

[2.8.3] - 2022-07-16

Improvements

• Support virtualized ARM64 macOS
• A switch to generate auxiliary events by async-profiler or FlightRecorder in jfrsync mode

Bug fixes

• Could not recreate perf_events after the first failure
• Handle different versions of Zing properly
• Do not call System.loadLibrary, when libasyncProfiler is preloaded

[2.8.2] - 2022-07-13

Bug fixes

• The same .so works with glibc and musl
• dlopen hook did not work on Arch Linux
• Fixed JDK 7 crash
• Fixed CPU profiling on Zing

Changes

• Mark interpreted frames with _[0] in collapsed output
• Double click selects a method name on a flame graph

[2.8.1] - 2022-06-10

Improvements

• JFR to pprof converter (contributed by @NeQuissimus)
• JFR converter improvements: time range, collapsed output, pattern highlighting
• %n pattern in file names; limit number of output files
• --lib to customize profiler library path in a container
• profiler.sh list command now works without PID

Bug fixes

• Fixed crashes related to continuous profiling
• Fixed Alpine/musl compatibility issues
• Fixed incomplete collapsed output due to weird locale settings
• Workaround for JDK-8185348

[2.8] - 2022-05-09

Features

• Mark top methods as interpreted, compiled (C1/C2), or inlined
• JVM TI based allocation profiling for JDK 11+
• Embedded HTTP management server

Improvements

• Re-implemented stack recovery for better reliability
• Add loglevel argument
• Do not mmap perf page in --all-user mode
• Distinguish runnable/sleeping threads in OpenJ9 wall-clock profiler
• --cpu converter option to extract CPU profile from the wall-clock output

[2.7] - 2022-02-14

Features

• Experimental support for OpenJ9 VM
• DWARF stack unwinding

Improvements

• Better handling of VM threads (fixed missing JIT threads)
• More reliable recovery from not_walkable AGCT failures
• Do not accept unknown agent arguments

[2.6] - 2022-01-09

Features

• Continuous profiling; loop and timeout options

Improvements

• Reliability improvements: avoid certain crashes and deadlocks
• Smaller and faster agent library
• Minor jfr and jfrsync enhancements (see the commit log)

[2.5.1] - 2021-12-05

Bug fixes

• Prevent early unloading of libasyncProfiler.so
• Read kernel symbols only for perf_events
• Escape backslashes in flame graphs
• Avoid duplicate categories in jfrsync mode
• Fixed stack overflow in RedefineClasses
• Fixed deadlock when flushing JFR

Improvements

• Support OpenJDK C++ Interpreter (aka Zero)
• Allow reading incomplete JFR recordings

[2.5] - 2021-10-01

Features

• macOS/ARM64 (aka Apple M1) port
• PPC64LE port (contributed by @ghaug)
• Profile low-privileged processes with perf_events (contributed by @Jongy)
• Raw PMU events; kprobes & uprobes
• Dump results in the middle of profiling session
• Chunked JFR; support JFR files larger than 2 GB
• Integrate async-profiler events with JDK Flight Recordings

Improvements

• Use RDTSC for JFR timestamps when possible
• Show line numbers and bci in Flame Graphs
• jfr2flame can produce Allocation and Lock flame graphs
• Flame Graph title depends on the event and --total
• Include profiler logs and native library list in JFR output
• Lock profiling no longer requires JVM symbols
• Better container support
• Native function profiler can count the specified argument
• An option to group threads by scheduling policy
• An option to prepend library name to native symbols

Notes

• macOS build is provided as a fat binary that works both on x86-64 and ARM64
• 32-bit binaries are no longer shipped. It is still possible to build them from sources
• Dropped JDK 6 support (may still work though)

[2.0] - 2021-03-14

Features

• Profile multiple events together (cpu + alloc + lock)
• HTML 5 Flame Graphs: faster rendering, smaller size
• JFR v2 output format, compatible with FlightRecorder API
• JFR to Flame Graph converter
• Automatically turn profiling on/off at --begin/--end functions
• Time-to-safepoint profiling: --ttsp

Improvements

• Unlimited frame buffer. Removed -b option and 64K stack traces limit
• Additional JFR events: OS, CPU, and JVM information; CPU load
• Record bytecode indices / line numbers
• Native stack traces for Java events
• Improved CLI experience
• Better error handling; an option to log warnings/errors to a dedicated stream
• Reduced the amount of unknown stack traces

Changes

• Removed non-ASL code. No more CDDL license

[1.8.4] - 2021-02-24

Improvements

• Smaller and faster agent library

Bug fixes

• Fixed JDK 7 crash during wall-clock profiling

[1.8.3] - 2021-01-06

Improvements

• libasyncProfiler.dylib symlink on macOS

Bug fixes

• Fixed possible deadlock on non-HotSpot JVMs
• Gracefully stop profiler when terminating JVM
• Fixed GetStackTrace problem after RedefineClasses

[1.8.2] - 2020-11-02

Improvements

• AArch64 build is now provided out of the box
• Compatibility with JDK 15 and JDK 16

Bug fixes

• More careful native stack walking in wall-clock mode
• resume command is not compatible with JFR format
• Wrong allocation sizes on JDK 8u262

[1.8.1] - 2020-09-05

Improvements

• Possibility to specify application name instead of pid (contributed by @yuzawa-san)

Bug fixes

• Fixed long attach time and slow class loading on JDK 8
• UnsatisfiedLinkError during Java method profiling
• Avoid reading /proc/kallsyms when --all-user is specified

[1.8] - 2020-08-10

Features

• Converters between different output formats:
  • JFR -> nflx (FlameScope)
  • Collapsed stacks -> HTML 5 Flame Graph

Improvements

• profiler.sh no longer requires bash (contributed by @cfstras)
• Fixed long attach time and slow class loading on JDK 8
• Fixed deadlocks in wall-clock profiling mode
• Per-thread reverse Flame Graph and Call Tree
• ARM build now works with ARM and THUMB flavors of JDK

Changes

• Release package is extracted into a separate folder

[1.7.1] - 2020-05-14

Features

• LBR call stack support (available since Haswell)

Improvements

• --filter to profile only specified thread IDs in wall-clock mode
• --safe-mode to disable selected stack recovery techniques

[1.7] - 2020-03-17

Features

• Profile invocations of arbitrary Java methods
• Filter stack traces by the given name pattern
• Java API to filter monitored threads
• --cstack/--no-cstack option

Improvements

• Thread names and Java thread IDs in JFR output
• Wall clock profiler distinguishes RUNNABLE vs. SLEEPING threads
• Stable profiling interval in wall clock mode
• C++ function names as events, e.g. -e VMThread::execute
• check command to test event availability
• Allow shading of AsyncProfiler API
• Enable CPU profiling on WSL
• Enable allocation profiling on Zing
• Reduce the amount of unknown_Java samples

[1.6] - 2019-09-09

Features

• Pause/resume profiling
• Allocation profiling support for JDK 12, 13 (contributed by @rraptorr)

Improvements

• Include all AsyncGetCallTrace failures in the profile
• Parse symbols of JNI libraries loaded in runtime
• The agent autodetects output format by the file extension
• Output file name patterns: %p and %t
• -g option to print method signatures
• -j can increase the maximum Java stack depth
• Allocaton sampling rate can be adjusted with -i
• Improved reliability on macOS

Changes

• -f file names are now relative to the current shell directory

[1.5] - 2019-01-08

Features

• Wall-clock profiler: -e wall
• -e itimer mode for systems that do not support perf_events
• Native stack traces on macOS
• Support for Zing runtime, except allocation profiling

Improvements

• --all-user option to allow profiling with restricted perf_event_paranoid (contributed by @jpbempel)
• -a option to annotate method names
• Improved attach to containerized and chroot'ed JVMs
• Native function profiling now accepts non-public symbols
• Better mapping of Java thread names (contributed by @KirillTim)

Changes

• Changed default profiling engine on macOS
• Fixed the order of stack frames in JFR format

[1.4] - 2018-06-24

Features

• Interactive Call tree and Backtrace tree in HTML format (contributed by @rpulle)
• Experimental support for Java Flight Recorder (JFR) compatible output

Improvements

• Added units: ms, us, s and multipliers: K, M, G for interval argument
• API and command-line option -v for profiler version
• Allow profiling containerized JVMs on older kernels

Changes

• Default CPU sampling interval reduced to 10 ms
• Changed the text format of flat profile

[1.3] - 2018-05-13

Features

• Profiling of native functions, e.g. malloc

Improvements

• JDK 9, 10, 11 support for heap profiling with accurate stack traces
• root can now profile Java processes of any user
• -j option for limiting Java stack depth

[1.2] - 2018-03-05

Features

• Produce SVG files out of the box; flamegraph.pl is no longer needed
• Profile ReentrantLock contention
• Java API

Improvements

• Allocation and Lock profiler now works on JDK 7, too
• Faster dumping of results

Changes

• total counter of allocation profiler now measures heap pressure (like JMC)

[1.1] - 2017-12-03

Features

• Linux Perf Events profiling: CPU cycles, cache misses, branch misses, page faults, context switches etc.
• Kernel tracepoints support
• Contended monitor (aka intrinsic lock) profiling
• Individual thread profiles

Improvements

• Profiler can engage at JVM start and automatically dump results on exit
• list command-line option to list supported events
• Automatically find target process ID with jps tool
• An option to include counter value in collapsed output
• Friendly class names in allocation profile
• Split allocations in new TLAB vs. outside TLAB

Changes

• Replaced -m modes with -e events
• Interval changed from int to long

[1.0] - 2017-10-09

Features

• CPU profiler without Safepoint bias
• Lightweight Allocation profiler
• Java, native and kernel stack traces
• FlameGraph compatible output