Cleanup

Author: alan-george-lk

.github/workflows/builds.yml

@@ -18,9 +18,6 @@ env:
   # incremental dirs add nothing but bloat the cached target/ directory and
   # slow the cache upload/download.
   CARGO_INCREMENTAL: "0"
-  # sccache uses this when the server starts. Set it at workflow scope so the
-  # probe step can actually start the server with the GitHub Actions backend.
-  SCCACHE_GHA_ENABLED: "true"
   # vcpkg binary caching for Windows. The x-gha backend was removed from vcpkg,
   # so use vcpkg's files provider and persist that directory with actions/cache.
   VCPKG_GIT_COMMIT: fb87e2bb3fe69e16c224989acb5a61349166c782
@@ -137,25 +134,6 @@ jobs:
         if: matrix.name == 'macos-x64'
         run: rustup target add x86_64-apple-darwin
 
-      # ---------- sccache experiment for Windows Rust builds ----------
-      - name: Setup sccache (Windows only)
-        if: runner.os == 'Windows'
-        uses: mozilla-actions/sccache-action@9e7fa8a12102821edf02ca5dbea1acd0f89a2696 # v0.0.10
-
-      - name: Enable sccache wrapping (Windows only)
-        id: sccache
-        if: runner.os == 'Windows'
-        shell: bash
-        run: |
-          if sccache --start-server >/dev/null 2>&1; then
-            echo "RUSTC_WRAPPER=sccache" >> "$GITHUB_ENV"
-            echo "enabled=true" >> "$GITHUB_OUTPUT"
-            echo "::notice::sccache enabled (RUSTC_WRAPPER=sccache)"
-          else
-            echo "enabled=false" >> "$GITHUB_OUTPUT"
-            echo "::warning::sccache backend unreachable; building without compile cache this run"
-          fi
-
       # ---------- Cache Cargo ----------
       # The Rust FFI is built from the pinned client-sdk-rust submodule. Its
       # compiled output only changes when the submodule commit changes, so we
@@ -201,11 +179,6 @@ jobs:
           LLVM_VERSION=$(llvm-config --version | cut -d. -f1)
           echo "LIBCLANG_PATH=/usr/lib/llvm-${LLVM_VERSION}/lib" >> "$GITHUB_ENV"
 
-      - name: Reset sccache stats (Windows only)
-        if: runner.os == 'Windows' && steps.sccache.outputs.enabled == 'true'
-        shell: bash
-        run: sccache --zero-stats
-
       # ---------- Build ----------
       - name: Build (Unix)
         if: runner.os != 'Windows'
@@ -219,18 +192,12 @@ jobs:
         shell: pwsh
         run: ${{ matrix.build_cmd }}
 
-      - name: Show sccache stats (Windows only)
-        if: always() && runner.os == 'Windows'
-        shell: bash
-        run: sccache --show-stats
-
       # Save the populated target/ now, while the build output still exists and
-      # before the "Clean after build" step runs clean-all. Only on a miss --
-      # an exact-key hit means the cache already holds this submodule's output.
-      # A restore-keys prefix hit still counts as a miss (cache-hit != 'true'),
-      # so a submodule bump always refreshes the cache under the new SHA.
+      # before the "Clean after build" step runs clean-all. Save only from main
+      # pushes so PRs restore from the shared main cache instead of creating
+      # large PR-scoped target caches that quickly evict useful entries.
       - name: Save cargo target
-        if: steps.cache-cargo-target.outputs.cache-hit != 'true'
+        if: github.event_name == 'push' && github.ref == 'refs/heads/main' && steps.cache-cargo-target.outputs.cache-hit != 'true'
         uses: actions/cache/save@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: client-sdk-rust/target/

.github/workflows/tests.yml

@@ -18,9 +18,6 @@ env:
   # incremental dirs add nothing but bloat the cached target/ directory and
   # slow the cache upload/download.
   CARGO_INCREMENTAL: "0"
-  # sccache uses this when the server starts. Set it at workflow scope so the
-  # probe step can actually start the server with the GitHub Actions backend.
-  SCCACHE_GHA_ENABLED: "true"
   # vcpkg binary caching for Windows (mirrors builds.yml). The x-gha backend
   # was removed from vcpkg, so use vcpkg's files provider and persist that
   # directory with actions/cache.
@@ -138,30 +135,11 @@ jobs:
         if: matrix.name == 'macos-x64'
         run: rustup target add x86_64-apple-darwin
 
-      # ---------- sccache experiment for Windows Rust builds ----------
-      - name: Setup sccache (Windows only)
-        if: runner.os == 'Windows'
-        uses: mozilla-actions/sccache-action@9e7fa8a12102821edf02ca5dbea1acd0f89a2696 # v0.0.10
-
-      - name: Enable sccache wrapping (Windows only)
-        id: sccache
-        if: runner.os == 'Windows'
-        shell: bash
-        run: |
-          if sccache --start-server >/dev/null 2>&1; then
-            echo "RUSTC_WRAPPER=sccache" >> "$GITHUB_ENV"
-            echo "enabled=true" >> "$GITHUB_OUTPUT"
-            echo "::notice::sccache enabled (RUSTC_WRAPPER=sccache)"
-          else
-            echo "enabled=false" >> "$GITHUB_OUTPUT"
-            echo "::warning::sccache backend unreachable; building without compile cache this run"
-          fi
-
       # ---------- Cache Cargo ----------
       # See builds.yml for the rationale: the Rust FFI output only changes with
       # the client-sdk-rust submodule commit, so key the target cache on the
-      # submodule SHA. The build workflow owns saving this cache; tests are
-      # restore-only to avoid same-key save races across parallel jobs.
+      # submodule SHA. Only main pushes save this cache; tests are restore-only
+      # to avoid same-key save races and PR-scoped cache churn.
       - name: Resolve Rust submodule SHA
         id: rust_sha
         shell: bash
@@ -196,11 +174,6 @@ jobs:
           LLVM_VERSION=$(llvm-config --version | cut -d. -f1)
           echo "LIBCLANG_PATH=/usr/lib/llvm-${LLVM_VERSION}/lib" >> "$GITHUB_ENV"
 
-      - name: Reset sccache stats (Windows only)
-        if: runner.os == 'Windows' && steps.sccache.outputs.enabled == 'true'
-        shell: bash
-        run: sccache --zero-stats
-
       # ---------- Build (release-tests: tests on, examples off) ----------
       - name: Build tests (Unix)
         if: runner.os != 'Windows'
@@ -214,11 +187,6 @@ jobs:
         shell: pwsh
         run: ${{ matrix.build_cmd }}
 
-      - name: Show sccache stats (Windows only)
-        if: always() && runner.os == 'Windows'
-        shell: bash
-        run: sccache --show-stats
-
       # ---------- Run unit tests ----------
       - name: Run unit tests (Unix)
         if: runner.os != 'Windows'