| OLD | NEW |
|---|
| 1 # MemoryInfra | 1 This document has moved to [//docs/memory-infra/README.md](/docs/memory-infra/RE
ADME.md). |
| 2 | 2 |
| 3 MemoryInfra is a timeline-based profiling system integrated in chrome://tracing. | |
| 4 It aims at creating Chrome-scale memory measurement tooling so that on any | |
| 5 Chrome in the world --- desktop, mobile, Chrome OS or any other --- with the | |
| 6 click of a button you can understand where memory is being used in your system. | |
| 7 | |
| 8 [TOC] | |
| 9 | |
| 10 ## Getting Started | |
| 11 | |
| 12 1. Get a bleeding-edge or tip-of-tree build of Chrome. | |
| 13 | |
| 14 2. [Record a trace as usual][record-trace]: open [chrome://tracing][tracing] | |
| 15 on Desktop Chrome or [chrome://inspect?tracing][inspect-tracing] to trace | |
| 16 Chrome for Android. | |
| 17 | |
| 18 3. Make sure to enable the **memory-infra** category on the right. | |
| 19 | |
| 20 ![Tick the memory-infra checkbox when recording a trace.][memory-infra-box
] | |
| 21 | |
| 22 4. For now, some subsystems only work if Chrome is started with the | |
| 23 `--no-sandbox` flag. | |
| 24 <!-- TODO(primiano) TODO(ssid): https://crbug.com/461788 --> | |
| 25 | |
| 26 [record-trace]: https://sites.google.com/a/chromium.org/dev/developers/how-t
os/trace-event-profiling-tool/recording-tracing-runs | |
| 27 [tracing]: chrome://tracing | |
| 28 [inspect-tracing]: chrome://inspect?tracing | |
| 29 [memory-infra-box]: https://storage.googleapis.com/chromium-docs.appspot.com/1c6
d1886584e7cc6ffed0d377f32023f8da53e02 | |
| 30 | |
| 31 ![Timeline View and Analysis View][tracing-views] | |
| 32 | |
| 33 After recording a trace, you will see the **timeline view**. Timeline view | |
| 34 shows: | |
| 35 | |
| 36 * Total resident memory grouped by process (at the top). | |
| 37 * Total resident memory grouped by subsystem (at the top). | |
| 38 * Allocated memory per subsystem for every process. | |
| 39 | |
| 40 Click one of the ![M][m-blue] dots to bring up the **analysis view**. Click | |
| 41 on a cell in analysis view to reveal more information about its subsystem. | |
| 42 PartitionAlloc for instance, has more details about its partitions. | |
| 43 | |
| 44 ![Component details for PartitionAlloc][partalloc-details] | |
| 45 | |
| 46 The purple ![M][m-purple] dots represent heavy dumps. In these dumps, components | |
| 47 can provide more details than in the regular dumps. The full details of the | |
| 48 MemoryInfra UI are explained in its [design doc][mi-ui-doc]. | |
| 49 | |
| 50 [tracing-views]: https://storage.googleapis.com/chromium-docs.appspot.com/db
12015bd262385f0f8bd69133330978a99da1ca | |
| 51 [m-blue]: https://storage.googleapis.com/chromium-docs.appspot.com/b6
0f342e38ff3a3767bbe4c8640d96a2d8bc864b | |
| 52 [partalloc-details]: https://storage.googleapis.com/chromium-docs.appspot.com/02
eade61d57c83f8ef8227965513456555fc3324 | |
| 53 [m-purple]: https://storage.googleapis.com/chromium-docs.appspot.com/d7
bdf4d16204c293688be2e5a0bcb2bf463dbbc3 | |
| 54 [mi-ui-doc]: https://docs.google.com/document/d/1b5BSBEd1oB-3zj_CBAQWiQZ
0cmI0HmjmXG-5iNveLqw/edit | |
| 55 | |
| 56 ## Columns | |
| 57 | |
| 58 **Columns in blue** reflect the amount of actual physical memory used by the | |
| 59 process. This is what exerts memory pressure on the system. | |
| 60 | |
| 61 * **Total Resident**: (TODO: document this). | |
| 62 * **Peak Total Resident**: (TODO: document this). | |
| 63 * **PSS**: (TODO: document this). | |
| 64 * **Private Dirty**: (TODO: document this). | |
| 65 * **Swapped**: (TODO: document this). | |
| 66 | |
| 67 **Columns in black** reflect a best estimation of the the amount of physical | |
| 68 memory used by various subsystems of Chrome. | |
| 69 | |
| 70 * **Blink GC**: Memory used by [Oilpan][oilpan]. | |
| 71 * **CC**: Memory used by the compositor. | |
| 72 See [cc/memory][cc-memory] for the full details. | |
| 73 * **Discardable**: (TODO: document this). | |
| 74 * **Font Caches**: (TODO: document this). | |
| 75 * **GPU** and **GPU Memory Buffer**: GPU memory and RAM used for GPU purposes. | |
| 76 See [GPU Memory Tracing][gpu-memory]. | |
| 77 * **LevelDB**: (TODO: document this). | |
| 78 * **Malloc**: Memory allocated by calls to `malloc`, or `new` for most | |
| 79 non-Blink objects. | |
| 80 * **PartitionAlloc**: Memory allocated via [PartitionAlloc][partalloc]. | |
| 81 Blink objects that are not managed by Oilpan are allocated with | |
| 82 PartitionAlloc. | |
| 83 * **Skia**: (TODO: document this). | |
| 84 * **SQLite**: (TODO: document this). | |
| 85 * **V8**: (TODO: document this). | |
| 86 * **Web Cache**: (TODO: document this). | |
| 87 | |
| 88 The **tracing column in gray** reports memory that is used to collect all of the | |
| 89 above information. This memory would not be used if tracing were not enabled, | |
| 90 and it is discounted from malloc and the blue columns. | |
| 91 | |
| 92 <!-- TODO(primiano): Improve this. https://crbug.com/??? --> | |
| 93 | |
| 94 [oilpan]: /third_party/WebKit/Source/platform/heap/BlinkGCDesign.md | |
| 95 [cc-memory]: /cc/memory.md | |
| 96 [gpu-memory]: memory_infra_gpu.md | |
| 97 [partalloc]: /third_party/WebKit/Source/wtf/allocator/PartitionAlloc.md | |
| 98 | |
| 99 ## Related Pages | |
| 100 | |
| 101 * [Adding MemoryInfra Tracing to a Component](adding_memory_infra_tracing.md) | |
| 102 * [GPU Memory Tracing](memory_infra_gpu.md) | |
| 103 * [Heap Profiler Internals](heap_profiler_internals.md) | |
| 104 * [Heap Profiling with MemoryInfra](heap_profiler.md) | |
| 105 * [Startup Tracing with MemoryInfra](memory_infra_startup_tracing.md) | |
| 106 | |
| 107 ## Rationale | |
| 108 | |
| 109 Another memory profiler? What is wrong with tool X? | |
| 110 Most of the existing tools: | |
| 111 | |
| 112 * Are hard to get working with Chrome. (Massive symbols, require OS-specific | |
| 113 tricks.) | |
| 114 * Lack Chrome-related context. | |
| 115 * Don't deal with multi-process scenarios. | |
| 116 | |
| 117 MemoryInfra leverages the existing tracing infrastructure in Chrome and provides | |
| 118 contextual data: | |
| 119 | |
| 120 * **It speaks Chrome slang.** | |
| 121 The Chromium codebase is instrumented. Its memory subsystems (allocators, | |
| 122 caches, etc.) uniformly report their stats into the trace in a way that can | |
| 123 be understood by Chrome developers. No more | |
| 124 `__gnu_cxx::new_allocator< std::_Rb_tree_node< std::pair< std::string const,
base::Value*>>> ::allocate`. | |
| 125 * **Timeline data that can be correlated with other events.** | |
| 126 Did memory suddenly increase during a specific Blink / V8 / HTML parsing | |
| 127 event? Which subsystem increased? Did memory not go down as expected after | |
| 128 closing a tab? Which other threads were active during a bloat? | |
| 129 * **Works out of the box on desktop and mobile.** | |
| 130 No recompilations with unmaintained `GYP_DEFINES`, no time-consuming | |
| 131 symbolizations stages. All the logic is already into Chrome, ready to dump at | |
| 132 any time. | |
| 133 * **The same technology is used for telemetry and the ChromePerf dashboard.** | |
| 134 See [the slides][chromeperf-slides] and take a look at | |
| 135 [some ChromePerf dashboards][chromeperf] and | |
| 136 [telemetry documentation][telemetry]. | |
| 137 | |
| 138 [chromeperf-slides]: https://docs.google.com/presentation/d/1OyxyT1sfg50lA36A7ib
Z7-bBRXI1kVlvCW0W9qAmM_0/present?slide=id.gde150139b_0_137 | |
| 139 [chromeperf]: https://chromeperf.appspot.com/report?sid=3b54e60c995165657
4e19252fadeca846813afe04453c98a49136af4c8820b8d | |
| 140 [telemetry]: https://catapult.gsrc.io/telemetry | |
| 141 | |
| 142 ## Development | |
| 143 | |
| 144 MemoryInfra is based on a simple and extensible architecture. See | |
| 145 [the slides][dp-slides] on how to get your subsystem reported in MemoryInfra, | |
| 146 or take a look at one of the existing examples such as | |
| 147 [malloc_dump_provider.cc][malloc-dp]. The crbug label is | |
| 148 [Hotlist-MemoryInfra][hotlist]. Don't hesitate to contact | |
| 149 [tracing@chromium.org][mailtracing] for questions and support. | |
| 150 | |
| 151 [dp-slides]: https://docs.google.com/presentation/d/1GI3HY3Mm5-Mvp6eZyVB0JiaJ-
u3L1MMJeKHJg4lxjEI/present?slide=id.g995514d5c_1_45 | |
| 152 [malloc-dp]: https://chromium.googlesource.com/chromium/src.git/+/master/base/
trace_event/malloc_dump_provider.cc | |
| 153 [hotlist]: https://code.google.com/p/chromium/issues/list?q=label:Hotlist-Me
moryInfra | |
| 154 [mailtracing]: mailto:tracing@chromium.org | |
| 155 | |
| 156 ## Design documents | |
| 157 | |
| 158 Architectural: | |
| 159 | |
| 160 <iframe width="100%" height="300px" src="https://docs.google.com/a/google.com/em
beddedfolderview?id=0B3KuDeqD-lVJfmp0cW1VcE5XVWNxZndxelV5T19kT2NFSndYZlNFbkFpc3p
Sa2VDN0hlMm8"> | |
| 161 </iframe> | |
| 162 | |
| 163 Chrome-side design docs: | |
| 164 | |
| 165 <iframe width="100%" height="300px" src="https://docs.google.com/a/google.com/em
beddedfolderview?id=0B3KuDeqD-lVJfndSa2dleUQtMnZDeWpPZk1JV0QtbVM5STkwWms4YThzQ0p
GTmU1QU9kNVk"> | |
| 166 </iframe> | |
| 167 | |
| 168 Catapult-side design docs: | |
| 169 | |
| 170 <iframe width="100%" height="300px" src="https://docs.google.com/a/google.com/em
beddedfolderview?id=0B3KuDeqD-lVJfm10bXd5YmRNWUpKOElOWS0xdU1tMmV1S3F4aHo0ZDJLTmt
GRy1qVnQtVWM"> | |
| 171 </iframe> | |
| OLD | NEW |
|---|
Chromium Code Reviews
Issue 2494063002:
Move memory docs to docs/memory-infra (Closed)
