v1.20.0

[godlygeek]

What's Changed

Features

• Add a light/dark theme toggle to the flame graph and table HTML reports, which respects the system color scheme and remembers the user's choice. (Dark Mode for Flame graph reports #650)
• Recognize deallocations performed with the free_sized and free_aligned_sized functions introduced in C23. (Intercept new free_sized and free_aligned_sized functions #725)
• Improve error reporting after a failure to record a memory capture by logging the reported error string and including it in the exception message. (Add more logging around error conditions #747)
• Add a --buffered-file-io option to memray run (and a buffered=True argument to memray.FileDestination) that writes the capture file using buffered write calls instead of the default memory-mapped file IO. This is useful on filesystems that don't support shared writable mmap, though it's slower and less robust to crashes. (Update the C++ FileSink to fall back to write() if memory mapping isn't supported #748)
• Add per-module allocation statistics to memray stats, showing the top allocating non-stdlib modules by size and by number of allocations. (Update memray stats to show the top 5 non-stdlib modules with the most allocations #765)
• When memray attach -o is used with --duration, print a message clarifying that tracking continues in the target process after the command exits, and how to stop it early with memray detach. (memray attach with --duration exits immediately instead of tracking for the given time #831)
• Add a speedscope output format for memray transform. (Add speedscope export timestamp fallback #899)
• Python 3.15 is now supported. (Support Python 3.15 #920)
• Added a --confidential-files option to memray flamegraph to control whether source code lines are embedded in the generated report. By default, Memray uses heuristics to guess whether each file is likely to contain secrets, and omits source lines from files that might. You can use --confidential-files=all to omit all source lines, or --confidential-files=none to include source lines from every file. See the docs on confidential source lines for more information. (Allow control over flame graph source inclusion #983)

Deprecations and Removals

• Memray no longer provides an entry point named memray3.N (where "3.N" is the Python version that Memray was installed for). You can use python3.N -m memray instead. (Use scikit-build  #673)
• Drop integration with 0.x versions of the greenlet module (which are from 2020 or earlier). (Fix greenlet integration with greenlet 3.4.0 #908)
• Drop support for Python 3.7, which reached end-of-life in June 2023. (Build and test Python 3.15 wheels with cibuildwheel #946)
• Drop support for Python 3.8, which reached end-of-life in October 2024. (Build and test Python 3.15 wheels with cibuildwheel #946)

Bug Fixes

• Fix an AttributeError crash on shutdown when tracking a script that calls gevent.monkey.patch_all() (or otherwise replaces threading.Thread while tracking). The Tracker now records the threading.Thread subclass it patched on entry and removes its instrumentation from that same class on exit, instead of looking up threading.Thread again. (Crash on gevent: AttributeError: type object 'Thread' has no attribute '_name' #856)
• Deduplicate rows in the table reporter that had identical displayed fields but different underlying call stacks. Also add a --split-threads option to the table reporter, matching the flamegraph reporter's existing option, and change the table reporter to no longer split allocations by thread by default. (Duplicate entries in memray table --leaks reporter. #857)
• Fix the %%memray_flamegraph Jupyter integration to correctly embed a flame graph for Python 3.12 and higher. Previously it was giving a 404 error due to tempfile.mkdtemp changing to return absolute paths. (Jupyter Integration not displaying the results. It returns 404 : Not Found #896)
• Fix integration with the greenlet package when greenlet 3.4.0 is installed and when tracing is started before the greenlet module is imported. (Fix greenlet integration with greenlet 3.4.0 #908)
• Fix a bug that crashed target processes when memray attach failed to dlopen our library. The underlying permissions issue is now accounted for and a troubleshooting message prints when it arises. (Add diagnostic message for missing permissions on attach #940)
• Fix a potential deadlock in the gdb backend for memray attach. (Fix deadlocks in the GDB attach script #966)
• Fix the %%memray_flamegraph Jupyter integration to correctly embed a flame graph when used with IPython 9.16.0 (a regression in that version broke our integration; it was fixed in IPython 9.16.1). (Pass IFrame path to IPython as a str #981)

Miscellaneous

• Memray is now built using scikit-build-core and CMake instead of setuptools. This should have little to no impact on end users, but redistributors like distro package maintainers will need to ensure that these tools are available when building Memray. (Use scikit-build  #673)
• Memray now provides manylinux_2_28 wheels for x86-64 as well as manylinux2014 ones (Begin building manylinux_2_28 wheels for x86-64 #967).

New Contributors

• @swaroski made their first contribution in Improve error messages when run command fails to find target #907
• @sthapa made their first contribution in gh-923: Update image to use trixie #928
• @tnytown made their first contribution in Address Zizmor findings and enable Zizmor in CI #922
• @Abdur-rahmaanJ made their first contribution in Solve #934: Add CONTRIBUTING link to README #935
• @albertchae made their first contribution in Add a GitHub Codespaces button to CONTRIBUTING.md #933
• @ikrommyd made their first contribution in Support Python 3.15 #927
• @grantlouisherman made their first contribution in Removing requirements-*.txt files in favor of dep groups #926
• @abhiojha8 made their first contribution in Deduplicate rows in table reporter with identical displayed fields #892
• @Do-yoon made their first contribution in feat: add light/dark theme toggle for HTML reports #939
• @naamanu made their first contribution in Add support for the new C23 deallocators #988

Full Changelog: v1.19.3...v1.20.0

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This discussion was created from the release v1.20.0.