Valgrind’s Memcheck tool works on Linux and MacOS, but not on Windows. Interestingly, there is something like it for Windows: “Dr Memory”. Similar in style to Memcheck, Dr Memory is an open source memory checking tool built on top of … Continue reading
One of the things I’ve been doing these past few months is running Mochitests on Valgrind on a semi-regular basis — roughly weekly — and trying to drive the resultant error count down to zero. I did this some years … Continue reading
Valgrind support on Yosemite has improved significantly in the past few months. It is now feasible to run Firefox on Valgrind on Yosemite. Support for 10.9 (Mavericks) has also improved, but 64-bit Yosemite remains the primary focus of support work. … Continue reading
Last August I asked the question “How fast can CFI/EXIDX-based stack unwinding be?” At the time I was experimenting with native unwinding using our in-tree Breakpad copy, but getting dismal performance results. The posting observed that Breakpad’s CFI unwinder is … Continue reading
In last week’s episode of The Wonderful World of CFI Unwinding we looked at how fast it could be done. This week we’re going to look at how compactly the unwind information can be stored. But I know you want … Continue reading
This is a long post. Here’s a summary. Valgrind unwinds CFI typically 30 times faster than Breakpad. Bad though that sounds, it’s really encouraging. If we can get even half that speedup — that is, 15 times faster than at … Continue reading
In short: more adaptation to real-use cases, and more unwind speedups. Benoit redid time-unit measurements so as to support profiling with sampling intervals of less than one millisecond. This will help profiling graphics and animation code (820048). Gijs Kruitbosch made … Continue reading
There’s been quite some progress since the last report, focussed on Firefox for Android. Anton Kovalyov landed changes to the GUI that show the event timelines for multiple threads in a synchronised way. The multithreaded aspects of the profiler are … Continue reading
Since the last report, work has focused on making multithreaded profiling more usable, using ARM EXIDX unwind data for Android nightlies, and more analysis of unwind failures. The latter two lines of investigation happened concurrently because there was some doubt … Continue reading
There has been a lot of activity since the previous report, mostly along three lines of development: multithreaded profiling, getting profiling working for Android nightlies, and improving the quality of the stack traces. We now have native unwinds working out-of-the-box … Continue reading
