• Seth Brenith's avatar
    Add option to report discarded allocations in sampling heap profiler · 3d59a3c2
    Seth Brenith authored
    A couple of customers have asked about using devtools to get information
    about temporary allocations, with the goal of reducing GC time and/or
    peak memory usage. Currently, the sampling heap profiler reports only
    objects which are still alive at the end of the profiling session. In
    this change, I propose adding configuration options when starting the
    sampling heap profiler so that it can optionally include information
    about objects which were discarded by the GC before the end of the
    profiling session. A user could run the sampling heap profiler in
    several different modes depending on their goals:
    
    1. To find memory leaks or determine which functions contribute most to
       steady-state memory consumption, the current default mode is best.
    2. To find functions which cause large temporary memory spikes or large
       GC pauses, the user can request data about both live objects and
       those collected by major GC.
    3. To tune for minimal GC activity in latency-sensitive applications
       like real-time audio processing, the user can request data about
       every allocation, including objects collected by major or minor GC.
    4. I'm not sure why anybody would want data about objects collected by
       minor GC and not objects collected by major GC, but it's also a valid
       flags combination.
    
    Change-Id: If55d5965a1de04fed3ae640a02ca369723f64fdf
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3868522Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
    Reviewed-by: 's avatarCamillo Bruni <cbruni@chromium.org>
    Reviewed-by: 's avatarSimon Zünd <szuend@chromium.org>
    Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
    Cr-Commit-Position: refs/heads/main@{#83202}
    3d59a3c2
v8-heap-profiler-agent-impl.cc 18.8 KB