These tools are for use by developers so that they can create more robust applications. Especially of use to those developing multi-threaded applications in C++ with templates. Includes TCMalloc, heap-checker, heap-profiler and cpu-profiler.

Recent news:

26 August 2011

I've just released perftools 1.8.3

The star-crossed 1.8 series continues; in 1.8.1, I had accidentally removed some code that was needed for FreeBSD. (Without this code many apps would crash at startup.) This release re-adds that code. If you are not on FreeBSD, or are using FreeBSD with perftools 1.8 or earlier, there is no need to upgrade.

11 August 2011

I've just released perftools 1.8.2

I was incorrectly calculating the patch-level in the configuration step, meaning the TC_VERSION_PATCH #define in tcmalloc.h was wrong. Since the testing framework checks for this, it was failing. Now it should work again. This time, I was careful to re-run my tests after upping the version number. :-)

If you don't care about the TC_VERSION_PATCH #define, there's no reason to upgrae.

26 July 2011

I've just released perftools 1.8.1

I was missing an #include that caused the build to break under some compilers, especially newer gcc's, that wanted it. This only affects people who build from source, so only the .tar.gz file is updated from perftools 1.8. If you didn't have any problems compiling perftools 1.8, there's no reason to upgrade.

15 July 2011

I've just released perftools 1.8

Of the many changes in this release, a good number pertain to porting. I've revamped OS X support to use the malloc-zone framework; it should now Just Work to link in tcmalloc, without needing DYLD_FORCE_FLAT_NAMESPACE or the like. (This is a pretty major change, so please feel free to report feedback at google-perftools@googlegroups.com.) 64-bit Windows support is also improved, as is ARM support, and the hooks are in place to improve FreeBSD support as well.

On the other hand, I'm seeing hanging tests on Cygwin. I see the same hanging even with (the old) perftools 1.7, so I'm guessing this is either a problem specific to my Cygwin installation, or nobody is trying to use perftools under Cygwin. If you can reproduce the problem, and even better have a solution, you can report it at google-perftools@googlegroups.com.

Internal changes include several performance and space-saving tweaks. One is user-visible (but in "stealth mode", and otherwise undocumented): you can compile with -DTCMALLOC_SMALL_BUT_SLOW. In this mode, tcmalloc will use less memory overhead, at the cost of running (likely not noticeably) slower.

There are many other changes as well, too numerous to recount here, but present in the ChangeLog.

7 February 2011

Thanks to endlessr..., who identified why some tests were failing under MSVC 10 in release mode. The problem was not with tcmalloc but with the test itself, which made some assumptions that broke under some aggressive (or possibly buggy) optimizations used in MSVC 10. I've fixed the test in svn, but even if using the 1.7 .zip file, feel free to compile perftools under MSVC 10.

4 February 2011

I've just released perftools 1.7

I apologize for the delay since the last release; so many great new patches and bugfixes kept coming in (and are still coming in; I also apologize to those folks who have to slip until the next release). I picked this arbitrary time to make a cut.

Among the many new features in this release is a multi-megabyte reduction in the amount of tcmalloc overhead uder x86_64, improved performance in the case of contention, and many many bugfixes, especially architecture-specific bugfixes. See the ChangeLog for full details.

One architecture-specific change of note is added comments in the README for using tcmalloc under OS X. I'm trying to get my head around the exact behavior of the OS X linker, and hope to have more improvements for the next release, but I hope these notes help folks who have been having trouble with tcmalloc on OS X.

Windows users: I've heard reports that some unittests fail on Windows when compiled with MSVC 10 in Release mode. All tests pass in Debug mode. I've not heard of any problems with earlier versions of MSVC. I don't know if this is a problem with the runtime patching (so the static patching discussed in README_windows.txt will still work), a problem with perftools more generally, or a bug in MSVC 10. Anyone with windows expertise that can debug this, I'd be glad to hear from!

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 INSTALL file; for all changes, see the 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 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 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 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 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!