)]}'
{
  "commit": "9d19a7870add65151ff91bcc26252bb7521065cf",
  "tree": "86c1257ea7f67113ee2dd769071b846194fc2315",
  "parents": [
    "651e16f083bb30729561be1e8bb994893fc2bb53"
  ],
  "author": {
    "name": "Takuto Ikuta",
    "email": "tikuta@google.com",
    "time": "Tue Feb 17 17:13:10 2026 +0900"
  },
  "committer": {
    "name": "GN LUCI",
    "email": "gn-scoped@luci-project-accounts.iam.gserviceaccount.com",
    "time": "Tue Feb 17 06:43:02 2026 -0800"
  },
  "message": "[perf] Share ResolvedTargetData across worker threads\n\nThis commit modifies ResolvedTargetData to be thread-safe using a\ncombination of std::shared_mutex for the target-to-info map and\nper-target mutexes with atomic flags for individual property\ncomputations (double-checked locking).\n\nBy sharing a single ResolvedTargetData instance across all worker\nthreads in command_gen.cc, we eliminate redundant computations of\ntransitive dependencies (libs, hard_deps, etc.) that were previously\nperformed independently by each thread.\n\nHyperfine benchmark results on a large Chromium build graph (gn gen):\n- main: 3.538 s ± 0.041 s [User: 18.883 s, System: 2.922 s]\n- shared: 2.894 s ± 0.041 s [User: 13.647 s, System: 3.072 s]\n- Improvement: ~22% faster wall-clock time, ~28% reduction in user CPU time.\n\nBug: 484863025\nChange-Id: Ib9c31feee6a118423b1bb6cf4e5552be660cb7c4\nReviewed-on: https://gn-review.googlesource.com/c/gn/+/21000\nCommit-Queue: Takuto Ikuta \u003ctikuta@google.com\u003e\nReviewed-by: David Turner \u003cdigit@google.com\u003e\n",
  "tree_diff": [
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}