Speed up with pytest-xdist

Author: hugovk

ubuntu-24.04-noble-amd64-valgrind/Dockerfile

@@ -43,7 +43,7 @@ ARG PIP_NO_CACHE_DIR=1
 
 RUN virtualenv -p /usr/bin/python3.12-dbg --system-site-packages /vpy3 \
     && /vpy3/bin/pip install --upgrade pip \
-    && /vpy3/bin/pip install olefile pytest pytest-cov pytest-timeout pytest-valgrind \
+    && /vpy3/bin/pip install olefile pytest pytest-cov pytest-timeout pytest-valgrind pytest-xdist \
     && chown -R pillow:pillow /vpy3
 
 COPY depends /depends

ubuntu-24.04-noble-amd64-valgrind/test.sh

@@ -4,9 +4,10 @@ cd /Pillow
 make clean
 make install-coverage
 
-PYTHONMALLOC=malloc valgrind --suppressions=/depends/python.supp --leak-check=no \
-            --log-file=/tmp/valgrind-output \
-            python3 -m pytest --no-memcheck -vv --valgrind --valgrind-log=/tmp/valgrind-output
+PYTHONMALLOC=malloc valgrind --trace-children=yes --trace-children-skip='*/gs' \
+            --suppressions=/depends/python.supp --leak-check=no \
+            --log-file=/tmp/valgrind-output.%p \
+            python3 -m pytest --no-memcheck -vv --valgrind -n auto
 
 # To run one test in the image:
 # make bash