diff --git a/.github/workflows/a3.yml b/.github/workflows/a3.yml
index 30097346b78..67972c178af 100644
--- a/.github/workflows/a3.yml
+++ b/.github/workflows/a3.yml
@@ -122,6 +122,7 @@ jobs:
     - name: pio build
       run: |
         set -x
+        alias mpiexec='mpiexec --oversubscribe'
         export PATH="/home/runner/openmpi/bin:$PATH"
         export CC=/home/runner/openmpi/bin/mpicc
         ./configure