diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index ff878850c..a684f6606 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -598,6 +598,16 @@ jobs:
         with:
           key: ubuntu-rocm-cmake-${{ matrix.ROCM_VERSION }}-${{ matrix.build }}
           evict-old-files: 1d
+          max-size: "2G"
+
+      - name: Tune ccache for reinstalled ROCm toolchain
+        run: |
+          # ROCm is pip-installed fresh each run, so the clang binary's mtime
+          # changes every time. With the default compiler_check=mtime that
+          # invalidates the cache; hash compiler contents instead so warm
+          # builds hit.
+          ccache --set-config=compiler_check=content
+          ccache --set-config=sloppiness=time_macros,include_file_mtime,include_file_ctime
 
       - name: Dependencies
         id: depends