tune parallelism

.config/nextest.toml

@@ -1,2 +1,5 @@
 [profile.default]
 slow-timeout = { period = "60s", terminate-after = 3 }
+
+test-threads = "num-cpus"
+threads-required = 8

.github/workflows/_build-and-test-locally.yml

@@ -46,7 +46,7 @@ jobs:
       # On 5.10 LTS kernels < 5.10.162 (and generally mainline kernels < 5.12),
       # io_uring will account the memory of the CQ and SQ as locked.
       # More details: https://github.com/neondatabase/neon/issues/6373#issuecomment-1905814391
-      options: --init --shm-size=512mb --ulimit memlock=67108864:67108864
+      options: --init --shm-size=512mb --ulimit memlock=33554432:33554432 # 32Gb, was 67108864:67108864
     env:
       BUILD_TYPE: ${{ inputs.build-type }}
       GIT_VERSION: ${{ github.event.pull_request.head.sha || github.sha }}
@@ -212,7 +212,6 @@ jobs:
       - name: Run rust tests
         env:
           NEXTEST_RETRIES: 3
-          NEXTEST_TEST_THREADS: num-cpus
         run: |
           PQ_LIB_DIR=$(pwd)/pg_install/v16/lib
           export PQ_LIB_DIR
@@ -266,7 +265,7 @@ jobs:
         username: ${{ secrets.NEON_DOCKERHUB_USERNAME }}
         password: ${{ secrets.NEON_DOCKERHUB_PASSWORD }}
       # for changed limits, see comments on `options:` earlier in this file
-      options: --init --shm-size=512mb --ulimit memlock=67108864:67108864
+      options: --init --shm-size=512mb --ulimit memlock=33554432:33554432 # 32Gb, was 67108864:67108864
     strategy:
       fail-fast: false
       matrix: