1 files changed, 10 insertions, 1 deletions
diff --git a/pre_commit/xargs.py b/pre_commit/xargs.py
index 31be6f3..a7493c0 100644
--- a/pre_commit/xargs.py
+++ b/pre_commit/xargs.py
@@ -25,6 +25,14 @@ TRet = TypeVar('TRet')
 
 def cpu_count() -> int:
     try:
+        # On systems that support it, this will return a more accurate count of
+        # usable CPUs for the current process, which will take into account
+        # cgroup limits
+        return len(os.sched_getaffinity(0))
+    except AttributeError:
+        pass
+
+    try:
         return multiprocessing.cpu_count()
     except NotImplementedError:
         return 1
@@ -170,7 +178,8 @@ def xargs(
         results = thread_map(run_cmd_partition, partitions)
 
         for proc_retcode, proc_out, _ in results:
-            retcode = max(retcode, proc_retcode)
+            if abs(proc_retcode) > abs(retcode):
+                retcode = proc_retcode
             stdout += proc_out
 
     return retcode, stdout