| # Graphics Memory Metrics |
| |
| The intent of this page is to provide more context and pointers to assess the |
| cost of Chromium's rendering. It is also meant to be used to complement to |
| warning in `//tools/metrics/histograms/metadata/memory/histograms.xml`. |
| |
| ## GPU Process and Private Memory Footprint |
| |
| **tl;dr:** Memory.Gpu.PrivateMemoryFootprint does **not** reflect memory used by |
| graphics buffers on all platforms. A rough breakdown of platforms follows: |
| |
| - **Android (including Android WebView), Linux, Chrome OS:** None of the |
| graphics buffers are accounted for. Only CPU-side memory is reflected. |
| - **Windows:** Graphics memory may be partially or fully accounted for. |
| - **macOS, Intel CPUs:** Graphics memory may be partially or fully accounted for. |
| - **macOS, ARM64:** We believe that graphics buffers are fully accounted for. |
| |
| In summary, ARM64 macOS is the only platform where we are reasonably confident |
| that all memory allocations are properly reflected in |
| Memory.Gpu.PrivateMemoryFootprint. |
| |
| **Caution:** Rendering is heavily platform-specific. Do not assume that changes |
| impacting a platform are reflected on another one. Even for macOS, there are |
| many hardware, OS and Chromium-level differences. For instance, as of early |
| 2024, rendering is performed using Metal on ARM64, and OpenGL on Intel mac |
| devices. |
