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diff --git a/chromium/docs/website/site/developers/leak-detection/index.md b/chromium/docs/website/site/developers/leak-detection/index.md deleted file mode 100644 index a380506068a..00000000000 --- a/chromium/docs/website/site/developers/leak-detection/index.md +++ /dev/null @@ -1,80 +0,0 @@ ---- -breadcrumbs: -- - /developers - - For Developers -page_name: leak-detection -title: Leak Detection ---- - -When launching a new feature it is important to consider doing manual inspection -to look for memory leaks since some types of leaks will not easily show up -during other testing, especially if they are slow leaks. This can avoid bugs -which are otherwise difficult to detect. - -You can look for memory leaks on Windows using ETW heap tracing using -[UIforETW](https://randomascii.wordpress.com/2015/09/01/xperf-basics-recording-a-trace-the-ultimate-easy-way/), -an open-source wrapper for Microsoft's ETW/WPT toolkit. To set up for heap -tracing you need to download and run UIforETW, then: - -* Click on Settings and set "Heap-profiled processes" to chrome.exe, - check "Chrome developer", then close Settings -* Change the tracing type (just below "Input tracing") to "Heap - tracing to file" -* Close all unnecessary programs including other copies of Chrome in - order to reduce the trace size and noise -* If you need to record allocations that happen during startup then - start tracing and then launch Chrome. If not then you should launch - Chrome and wait for its startup activity to calm down. If you launch - Chrome with a minimal set of tabs then this will reduce the trace - size and noise -* When you are ready to test your feature then type Ctrl+Win+R (with - any window active) or click "Start Tracing" in UIforETW -* Run your test a few times, let Chrome go idle again, and then type - Ctrl+Win+R (with any window active) or click "Save Trace Buffers" in - UIforETW - -Tips for efficient tracing: - -* If you want to just heap-profile a renderer process then you should - launch Chrome *before* setting the tracing type. This will ensure - that heap tracing is disabled for the browser, GPU, utility, - extension, crashpad, and watcher processes. Only processes launched - *after* you change the tracing type to "Heap tracing to file" will - be heap traced, and only allocations/frees done after you start - tracing will be recorded. -* If you are only going to be looking at heap data then uncheck - "Context switch call stacks" and "CPU sampling call stacks" in order - to keep the trace as small as possible - -These trace analysis instructions are very terse because a full explanation -would require many pages. If you need assistance then please contact -brucedawson@chromium.org. - -If you have Python installed then IdentifyChromeProcesses.py will be run and a -list of Chrome process types and PIDs will be printed, which helps with -identifying the browser process, etc. If you need to identify a specific render -process PID then use Chrome's Task Manager. You can copy the trace to a -different machine for analysis, and you can manually run -IdentifyChromeProcesses.py on that machine by right-clicking on the trace name -and selecting Scripts-> Identify Chrome Processes. - -Open the trace in WPA. The default view is designed for analyzing performance -rather than allocations so you will want to use HeapAnalysis.wpaProfile from -UIforETW's bin directory (available in versions published in September 2018 or -later). You can apply this profile by going to the Profiles menu in WPA, -selecting Apply... and then browsing to the .wpaProfile file. Load symbols -(Trace-> Load Symbols) and you can then drill down into the allocations for -the process of interest. The Type column will usually list AIFI and AIFO types. -AIFI means Allocated Inside and Freed Inside - meaning that the allocation was -transient within the visible time range. AIFO means Allocated Inside and Freed -Outside meaning that the memory was allocated but not freed within the visible -time range. AIFO allocations are potential leaks. You can drill down through the -stack, sorting by Count, or Size, or you can search for particular symbols by -typing Ctrl+F when the Stack column is selected. - -The allocation times for the selected portion of stack will be highlighted in -the graph area, giving clues to patterns. These can be compared against input -events emitted by UIforETW.exe. - -It is also possible to use Visual Studio's heap profiler. This is particularly -convenient for profiling the browser process at startup.
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