diff --git a/.github/workflows/push_pull.yml b/.github/workflows/push_pull.yml
index 3cbd6fc2d4..7e0fce60c4 100644
--- a/.github/workflows/push_pull.yml
+++ b/.github/workflows/push_pull.yml
@@ -39,7 +39,7 @@ jobs:
       credentials:
          username: ${{ github.actor }}
          password: ${{ secrets.github_token }}
-      options: --cpus 2
+      options: --cpus 4
     steps:
       - name: Checkout
         uses: actions/checkout@main
@@ -55,8 +55,8 @@ jobs:
       - name: Build and check
         uses: ./.github/actions/build_and_check
         env:
-          build_procs: 2
-          check_procs: 2
+          build_procs: 4
+          check_procs: 4
           myconfig: 'maxset'
           with_ccache: 'true'
           with_cuda: 'false'
@@ -78,7 +78,7 @@ jobs:
       credentials:
          username: ${{ github.actor }}
          password: ${{ secrets.github_token }}
-      options: --cpus 2
+      options: --cpus 4
     steps:
       - name: Checkout
         uses: actions/checkout@main
@@ -94,8 +94,8 @@ jobs:
       - name: Build and check
         uses: ./.github/actions/build_and_check
         env:
-          build_procs: 2
-          check_procs: 2
+          build_procs: 4
+          check_procs: 4
           myconfig: 'maxset'
           with_ccache: 'true'
           with_cuda: 'false'
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 06e29ace6f..d374aaa4d0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -372,13 +372,16 @@ else()
 endif()
 
 # OpenMPI checks the number of processes against the number of CPUs
-set(ESPRESSO_MPIEXEC_OVERSUBSCRIBE "")
+set(ESPRESSO_MPIEXEC_PREFLAGS "")
 # Open MPI 4.x has a bug on NUMA archs that prevents running in singleton mode
 set(ESPRESSO_MPIEXEC_GUARD_SINGLETON_NUMA OFF)
 set(ESPRESSO_CPU_MODEL_NAME_OMPI_SINGLETON_NUMA_PATTERN "AMD (EPYC|Ryzen)")
 
 if("${ESPRESSO_MPIEXEC_VENDOR}" STREQUAL "OpenMPI")
-  set(ESPRESSO_MPIEXEC_OVERSUBSCRIBE "-oversubscribe")
+  list(APPEND ESPRESSO_MPIEXEC_PREFLAGS "--oversubscribe")
+  if(ESPRESSO_INSIDE_DOCKER)
+    list(APPEND ESPRESSO_MPIEXEC_PREFLAGS "--bind-to" "none")
+  endif()
   if(${ESPRESSO_MPIEXEC_VERSION} VERSION_LESS 5.0)
     if(NOT DEFINED ESPRESSO_CPU_MODEL_NAME)
       if(CMAKE_SYSTEM_NAME STREQUAL Linux)
diff --git a/cmake/espresso_unit_test.cmake b/cmake/espresso_unit_test.cmake
index c857d9bed1..daa07218b0 100644
--- a/cmake/espresso_unit_test.cmake
+++ b/cmake/espresso_unit_test.cmake
@@ -52,7 +52,7 @@ function(ESPRESSO_UNIT_TEST)
       set(TEST_NUM_PROC ${ESPRESSO_TEST_NP})
     endif()
     espresso_set_mpiexec_tmpdir(${TEST_NAME})
-    add_test(${TEST_NAME} ${MPIEXEC} ${ESPRESSO_MPIEXEC_OVERSUBSCRIBE}
+    add_test(${TEST_NAME} ${MPIEXEC} ${ESPRESSO_MPIEXEC_PREFLAGS}
              ${MPIEXEC_NUMPROC_FLAG} ${TEST_NUM_PROC} ${MPIEXEC_PREFLAGS}
              ${ESPRESSO_MPIEXEC_TMPDIR} ${CMAKE_CURRENT_BINARY_DIR}/${TEST_NAME}
              ${MPIEXEC_POSTFLAGS})
diff --git a/maintainer/CI/build_cmake.sh b/maintainer/CI/build_cmake.sh
index 4d4ce68d15..b155ed8c62 100755
--- a/maintainer/CI/build_cmake.sh
+++ b/maintainer/CI/build_cmake.sh
@@ -79,20 +79,14 @@ ci_procs=2
 if [ "${GITLAB_CI}" = "true" ]; then
     if [[ "${OSTYPE}" == "linux-gnu"* ]]; then
         # Linux runner
-        if grep -q "i7-3820" /proc/cpuinfo; then
-            # communication bottleneck for more than 2 cores on Intel i7-3820
-            ci_procs=2
-        else
-            ci_procs=4
-        fi
+        ci_procs=4
     elif [[ "${OSTYPE}" == "darwin"* ]]; then
         # macOS runner
-        ci_procs=2
+        ci_procs=4
     fi
 elif [ "${GITHUB_ACTIONS}" = "true" ]; then
-    # GitHub Actions only provide 1 core; request 2 cores to run tests
-    # in parallel (OpenMPI allows oversubscription)
-    ci_procs=2
+    # GitHub Actions provide 4 cores
+    ci_procs=4
 else
     ci_procs=$(nproc)
 fi
@@ -131,7 +125,6 @@ set_default_value with_walberla_avx false
 set_default_value with_stokesian_dynamics false
 set_default_value test_timeout 500
 set_default_value hide_gpu false
-set_default_value mpiexec_preflags ""
 
 if [ "${make_check_unit_tests}" = true ] || [ "${make_check_python}" = true ] || [ "${make_check_tutorials}" = true ] || [ "${make_check_samples}" = true ] || [ "${make_check_benchmarks}" = true ]; then
     run_checks=true
@@ -166,9 +159,6 @@ if [ "${with_walberla}" = true ]; then
   if [ "${with_walberla_avx}" = true ]; then
     cmake_params="${cmake_params} -D ESPRESSO_BUILD_WITH_WALBERLA_AVX=ON"
   fi
-  # disable default OpenMPI CPU binding mechanism to avoid stale references to
-  # waLBerla objects when multiple LB python tests run in parallel on NUMA archs
-  mpiexec_preflags="${mpiexec_preflags:+$mpiexec_preflags;}--bind-to;none"
 fi
 
 cmake_params="${cmake_params} -D ESPRESSO_BUILD_WITH_COVERAGE=${with_coverage}"
@@ -328,7 +318,7 @@ else
     if [ "${check_proc_particle_test}" -gt 4 ]; then
       check_proc_particle_test=4
     fi
-    mpiexec -n ${check_proc_particle_test} ./pypresso "${srcdir}/testsuite/python/particle.py" || exit 1
+    mpiexec -n ${check_proc_particle_test} $(mpiexec --version | grep -Pq "\\(Open(RTE| MPI)\\)" && echo "--oversubscribe --bind-to none") ./pypresso "${srcdir}/testsuite/python/particle.py" || exit 1
 
     end "TEST"
 fi
diff --git a/maintainer/benchmarks/CMakeLists.txt b/maintainer/benchmarks/CMakeLists.txt
index ea6c0c5f48..63c04f57fb 100644
--- a/maintainer/benchmarks/CMakeLists.txt
+++ b/maintainer/benchmarks/CMakeLists.txt
@@ -28,9 +28,9 @@ if(EXISTS ${MPIEXEC})
     OUTPUT_VARIABLE mpi_version_output ERROR_VARIABLE mpi_version_output)
   if(mpi_version_result EQUAL 0 AND mpi_version_output MATCHES
                                     "\\(Open(RTE| MPI)\\) ([3-9]\\.|1[0-9])")
-    set(ESPRESSO_MPIEXEC_OVERSUBSCRIBE "-oversubscribe")
+    set(ESPRESSO_MPIEXEC_PREFLAGS "--oversubscribe")
   else()
-    set(ESPRESSO_MPIEXEC_OVERSUBSCRIBE "")
+    set(ESPRESSO_MPIEXEC_PREFLAGS "")
   endif()
 endif()
 
@@ -86,7 +86,7 @@ function(PYTHON_BENCHMARK)
       add_test(
         NAME ${BENCHMARK_TEST_NAME}
         COMMAND
-          ${MPIEXEC} ${ESPRESSO_MPIEXEC_OVERSUBSCRIBE} ${MPIEXEC_NUMPROC_FLAG}
+          ${MPIEXEC} ${ESPRESSO_MPIEXEC_PREFLAGS} ${MPIEXEC_NUMPROC_FLAG}
           ${BENCHMARK_NUM_PROC} ${MPIEXEC_PREFLAGS}
           ${CMAKE_BINARY_DIR}/pypresso ${BENCHMARK_FILE} ${BENCHMARK_ARGUMENTS}
           ${MPIEXEC_POSTFLAGS})
diff --git a/samples/drude_bmimpf6.py b/samples/drude_bmimpf6.py
index fa07f15643..86c6c5215f 100644
--- a/samples/drude_bmimpf6.py
+++ b/samples/drude_bmimpf6.py
@@ -107,7 +107,7 @@
 
 # TIMESTEP
 fs_to_md_time = 1.0e-2
-time_step_fs = 1.0
+time_step_fs = 0.5
 time_step_ns = time_step_fs * 1e-6
 dt = time_step_fs * fs_to_md_time
 system.time_step = dt
@@ -229,7 +229,7 @@ def combination_rule_sigma(rule, sig1, sig2):
 # ENERGY MINIMIZATION
 print("\n-->E minimization")
 print(f"Before: {system.analysis.energy()['total']:.2e}")
-n_max_steps = 100000
+n_max_steps = 10000
 system.integrator.set_steepest_descent(f_max=5.0, gamma=0.01,
                                        max_displacement=0.01)
 system.integrator.run(n_max_steps)
diff --git a/testsuite/python/CMakeLists.txt b/testsuite/python/CMakeLists.txt
index 2fa3fa7977..ee90256b07 100644
--- a/testsuite/python/CMakeLists.txt
+++ b/testsuite/python/CMakeLists.txt
@@ -92,7 +92,7 @@ function(python_test)
     add_test(
       NAME ${TEST_NAME}
       COMMAND
-        ${MPIEXEC} ${ESPRESSO_MPIEXEC_OVERSUBSCRIBE} ${MPIEXEC_NUMPROC_FLAG}
+        ${MPIEXEC} ${ESPRESSO_MPIEXEC_PREFLAGS} ${MPIEXEC_NUMPROC_FLAG}
         ${TEST_NUM_PROC} ${MPIEXEC_PREFLAGS} ${ESPRESSO_MPIEXEC_TMPDIR}
         ${CMAKE_BINARY_DIR}/pypresso ${PYPRESSO_OPTIONS}
         ${TEST_FILE_CONFIGURED} ${TEST_ARGUMENTS} ${MPIEXEC_POSTFLAGS})
diff --git a/testsuite/python/resources.json b/testsuite/python/resources.json
index 906149627d..db5acbeff3 100644
--- a/testsuite/python/resources.json
+++ b/testsuite/python/resources.json
@@ -8,7 +8,7 @@
       "gpus": [
         {
           "id": "0",
-          "slots": 4
+          "slots": 8
         }
       ]
     }