)]}'
{
  "commit": "9f89475e80fc3cf1858e115be7462fb4f12e560c",
  "tree": "1eb6a237385b341c2003dbb39f095046d396dd98",
  "parents": [
    "60f173160384d96c690ecd29728105ad95ee665c"
  ],
  "author": {
    "name": "Abseil Team",
    "email": "absl-team@google.com",
    "time": "Thu Oct 22 00:36:31 2026 -0700"
  },
  "committer": {
    "name": "Copybara-Service",
    "email": "copybara-worker@google.com",
    "time": "Thu Oct 22 12:38:07 2026 -0700"
  },
  "message": "Pool `LogMessageData` instances in a 16-slot lock-free `ObjectPool` and lazily initialize `std::ostream` in `LogMessage`.\n\nEvery active `LOG(...)` statement previously allocated a ~30.5 KB `LogMessageData` buffer from the global heap (`std::make_unique\u003cLogMessageData\u003e`) and constructed and destroyed a `std::ostream` (`std::basic_ios::init` / `std::ios_base::~ios_base`) on every log statement, even when no `std::ostream` insertion operator or I/O manipulator was used.\n\n1. Introduce `absl::log_internal::ObjectPool\u003cT, kCapacity\u003e` in `log/internal/object_pool.h`, a cacheline-aligned, `ABSL_CONST_INIT`-compatible, trivially destructible lock-free object pool probed from a `thread_local` slot hint (or `GetCachedTID() % kCapacity` when `ABSL_HAVE_THREAD_LOCAL` is unavailable), falling back to `std::make_unique\u003cT\u003e` and `delete` when all `kCapacity` slots are concurrently in use. Use `ObjectPool\u003cLogMessageData, 16\u003e` (`LogMessageData::pool`) and `LogMessageData::Reset` to reuse `LogMessageData` instances across `LogMessage` lifetimes without touching the two 15 KB buffers (`encoded_buf` and `string_buf`).\n2. Change `LogMessageData::manipulated` from `std::ostream` to `std::optional\u003cstd::ostream\u003e` with a per-message `manipulated_used` flag, lazily constructing `std::ostream(nullptr)` on first `OstreamView` use in a `LogMessageData` slot and resetting stream formatting state (`clear`, `flags`, `precision`, `width`, `fill`) once per `LogMessage` when `OstreamView` is entered.\n\nPiperOrigin-RevId: 1004554083\n",
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