ci: speed up debug-tools workflow build (#9599)

Use the perf profile instead of release, merge qdrant and edge tool builds
into one cargo invocation, and add sccache so shared deps compile once and
rustc outputs are cached across runs.

Co-authored-by: Cursor <cursoragent@cursor.com>

.github/workflows/debug-tools.yml

@@ -25,14 +25,19 @@ permissions:
 
 env:
   CARGO_TERM_COLOR: always
+  RUSTC_WRAPPER: sccache
+  SCCACHE_GHA_ENABLED: "true"
   # Tools in the main `qdrant` crate, gated behind its `service_debug` feature.
   # Keep this list in sync with the `service_debug` [[bin]] targets in Cargo.toml
   DEBUG_BINS: wal_inspector wal_pop segment_inspector schema_generator model_testing
-  # Standalone tool crates (own workspace member, no `service_debug` feature),
-  # built with `-p`. Bin name must match the crate name.
+  # Standalone tool crates (own workspace member), built with `-p`.
+  # Bin name must match the crate name. Built in the same invocation as the
+  # qdrant bins so Cargo unifies features and shared workspace crates compile once.
   EDGE_BINS: edge-shard-query
   # Static target so the binaries run everywhere
   TARGET: x86_64-unknown-linux-musl
+  # Faster to compile than release (no fat LTO); still opt-level 3. See [profile.perf].
+  PROFILE: perf
   # ---- Adjust to your GCS bucket ----
   GCS_BUCKET: qdrant-debug
   GCS_ENDPOINT: https://storage.googleapis.com
@@ -61,29 +66,30 @@ jobs:
         uses: taiki-e/setup-cross-toolchain-action@3d9770ce98eb7dbcf378563182a5e8031165f75b # v1.41.0
         with:
           target: x86_64-unknown-linux-musl
+      - name: Setup sccache
+        uses: mozilla-actions/sccache-action@1583d6b38d7be47f593cb472781bbb21cab4321e # v0.0.10
       - uses: Swatinem/rust-cache@e18b497796c12c097a38f9edb9d0641fb99eee32 # v2
         with:
-          # Namespace the cache per target so the musl build doesn't collide with gnu caches
-          key: ${{ env.TARGET }}
+          # Namespace cache per target/profile so musl perf doesn't collide with gnu/release caches
+          key: ${{ env.TARGET }}-${{ env.PROFILE }}
           # Only save the cache on dev; feature-branch caches would just get evicted under the 10 GB budget
           save-if: ${{ (inputs.branch || github.ref_name) == 'dev' }}
 
       - name: Build debug tools
         run: |
-          # Tools in the qdrant crate (need the service_debug feature)
-          cargo build --release --locked --features service_debug \
-            --target "$TARGET" \
-            $(printf -- '--bin %s ' $DEBUG_BINS)
-          # Standalone tool crates (no service_debug feature)
-          cargo build --release --locked \
+          # Single build: `--features service_debug` applies to the qdrant bins;
+          # edge tools share the unified dependency graph (no second compile pass).
+          cargo build --profile "$PROFILE" --locked --features service_debug \
             --target "$TARGET" \
+            $(printf -- '--bin %s ' $DEBUG_BINS) \
             $(printf -- '-p %s ' $EDGE_BINS)
+          sccache --show-stats
 
       - name: Collect binaries
         run: |
           mkdir -p debug-tools
           for bin in $DEBUG_BINS $EDGE_BINS; do
-            cp "target/$TARGET/release/$bin" debug-tools/
+            cp "target/$TARGET/$PROFILE/$bin" debug-tools/
           done
 
       - name: Upload to GCS