Enable loadtest with PgBouncer (#3143)

* enable loadtest with pgbouncer

* use default_query_exec_mode=cache_describe for pgbouncer

* increase threshold

* make sure no regression

.github/workflows/test.yml

@@ -339,6 +339,50 @@ jobs:
           TESTING_MATRIX_PG_VERSION: ${{ matrix.pg-version }}
           TESTING_MATRIX_OPTIMISTIC_SCHEDULING: ${{ matrix.optimistic-scheduling }}
 
+  load-pgbouncer:
+    runs-on: ubicloud-standard-8
+    timeout-minutes: 30
+    strategy:
+      matrix:
+        migrate-strategy: ["latest"]
+        rabbitmq-enabled: ["true"]
+        pg-version: ["17-alpine"]
+        optimistic-scheduling: ["true", "false"]
+
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+
+      - name: Install Task
+        uses: arduino/setup-task@b91d5d2c96a56797b48ac1e0e89220bf64044611 # v2.0.0
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Setup Go
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
+        with:
+          go-version: "1.25"
+
+      - name: Setup pnpm
+        uses: pnpm/action-setup@41ff72655975bd51cab0327fa583b6e92b6d3061 # v4.2.0
+        with:
+          version: 10.16.1
+          run_install: false
+
+      - name: Go deps
+        run: go mod download
+
+      - name: Test
+        run: |
+          # Disable gzip compression for load tests to reduce CPU overhead
+          # Compression adds overhead without benefit for 0kb payloads
+          HATCHET_CLIENT_DISABLE_GZIP_COMPRESSION=true go test -tags load ./... -p 5 -v -race -failfast -timeout 20m
+        env:
+          TESTING_MATRIX_MIGRATE: ${{ matrix.migrate-strategy }}
+          TESTING_MATRIX_RABBITMQ_ENABLED: ${{ matrix.rabbitmq-enabled }}
+          TESTING_MATRIX_PG_VERSION: ${{ matrix.pg-version }}
+          TESTING_MATRIX_OPTIMISTIC_SCHEDULING: ${{ matrix.optimistic-scheduling }}
+          TESTING_MATRIX_PGBOUNCER_ENABLED: "true"
+
   load-online-migrate:
     runs-on: ubicloud-standard-8
     timeout-minutes: 30