=== 5 August 2010 === I've just released perftools 1.6 This version also has a large number of minor changes, including support for `malloc_usable_size()` as a glibc-compatible alias to `malloc_size()`, the addition of SVG-based output to `pprof`, and experimental support for tcmalloc large pages, which may speed up tcmalloc at the cost of greater memory use. To use tcmalloc large pages, see the [http://google-perftools.googlecode.com/svn/tags/perftools-1.6/INSTALL INSTALL file]; for all changes, see the [http://google-perftools.googlecode.com/svn/tags/perftools-1.6/ChangeLog ChangeLog]. OS X NOTE: improvements in the profiler unittest have turned up an OS X issue: in multithreaded programs, it seems that OS X often delivers the profiling signal (from sigitimer()) to the main thread, even when it's sleeping, rather than spawned threads that are doing actual work. If anyone knows details of how OS X handles SIGPROF events (from setitimer) in threaded programs, and has insight into this problem, please send mail to google-perftools@googlegroups.com. To see if you're affected by this, look for profiling time that pprof attributes to `___semwait_signal`. This is work being done in other threads, that is being attributed to sleeping-time in the main thread. === 20 January 2010 === I've just released perftools 1.5 This version has a slew of changes, leading to somewhat faster performance and improvements in portability. It adds features like `ITIMER_REAL` support to the cpu profiler, and `tc_set_new_mode` to mimic the windows function of the same name. Full details are in the [http://google-perftools.googlecode.com/svn/tags/perftools-1.5/ChangeLog ChangeLog]. === 11 September 2009 === I've just released perftools 1.4 The major change this release is the addition of a debugging malloc library! If you link with `libtcmalloc_debug.so` instead of `libtcmalloc.so` (and likewise for the `minimal` variants) you'll get a debugging malloc, which will catch double-frees, writes to freed data, `free`/`delete` and `delete`/`delete[]` mismatches, and even (optionally) writes past the end of an allocated block. We plan to do more with this library in the future, including supporting it on Windows, and adding the ability to use the debugging library with your default malloc in addition to using it with tcmalloc. There are also the usual complement of bug fixes, documented in the ChangeLog, and a few minor user-tunable knobs added to components like the system allocator. === 9 June 2009 === I've just released perftools 1.3 Like 1.2, this has a variety of bug fixes, especially related to the Windows build. One of my bugfixes is to undo the weird `ld -r` fix to `.a` files that I introduced in perftools 1.2: it caused problems on too many platforms. I've reverted back to normal `.a` files. To work around the original problem that prompted the `ld -r` fix, I now provide `libtcmalloc_and_profiler.a`, for folks who want to link in both. The most interesting API change is that I now not only override `malloc`/`free`/etc, I also expose them via a unique set of symbols: `tc_malloc`/`tc_free`/etc. This enables clients to write their own memory wrappers that use tcmalloc: {{{ void* malloc(size_t size) { void* r = tc_malloc(size); Log(r); return r; } }}} === 17 April 2009 === I've just released perftools 1.2. This is mostly a bugfix release. The major change is internal: I have a new system for creating packages, which allows me to create 64-bit packages. (I still don't do that for perftools, because there is still no great 64-bit solution, with libunwind still giving problems and --disable-frame-pointers not practical in every environment.) Another interesting change involves Windows: a [http://code.google.com/p/google-perftools/issues/detail?id=126 new patch] allows users to choose to override malloc/free/etc on Windows rather than patching, as is done now. This can be used to create custom CRTs. My fix for this [http://groups.google.com/group/google-perftools/browse_thread/thread/1ff9b50043090d9d/a59210c4206f2060?lnk=gst&q=dynamic#a59210c4206f2060 bug involving static linking] ended up being to make libtcmalloc.a and libperftools.a a big .o file, rather than a true `ar` archive. This should not yield any problems in practice -- in fact, it should be better, since the heap profiler, leak checker, and cpu profiler will now all work even with the static libraries -- but if you find it does, please file a bug report. Finally, the profile_handler_unittest provided in the perftools testsuite (new in this release) is failing on FreeBSD. The end-to-end test that uses the profile-handler is passing, so I suspect the problem may be with the test, not the perftools code itself. However, I do not know enough about how itimers work on FreeBSD to be able to debug it. If you can figure it out, please let me know! === 11 March 2009 === I've just released perftools 1.1! It has many changes since perftools 1.0 including * Faster performance due to dynamically sized thread caches * Better heap-sampling for more realistic profiles * Improved support on Windows (MSVC 7.1 and cygwin) * Better stacktraces in linux (using VDSO) * Many bug fixes and feature requests Note: if you use the CPU-profiler with applications that fork without doing an exec right afterwards, please see the README. Recent testing has shown that profiles are unreliable in that case. The problem has existed since the first release of perftools. We expect to have a fix for perftools 1.2. For more details, see [http://code.google.com/p/google-perftools/issues/detail?id=105 issue 105]. Everyone who uses perftools 1.0 is encouraged to upgrade to perftools 1.1. If you see any problems with the new release, please file a bug report at http://code.google.com/p/google-perftools/issues/list. Enjoy!