diff --git a/run.py b/run.py
index af7d2c6c..082e5c3d 100755
--- a/run.py
+++ b/run.py
@@ -18,7 +18,7 @@ if project_dir not in sys.path:
 # stay): the in-process twin of the unit's MALLOC_ARENA_MAX=2, for units
 # installed before that line. A no-op off glibc. See src/malloc_tuning.py.
 from src import malloc_tuning
-malloc_tuning.cap_arenas()
+print('EXP cap_arenas=%s' % malloc_tuning.cap_arenas(), flush=True)
 
 # Under systemd the watchdog clock is already running, and start-up (plugin
 # loads, initial updates) takes far longer than the render loop's limit. Widen
diff --git a/src/malloc_tuning.py b/src/malloc_tuning.py
index 95d96155..8af5861f 100644
--- a/src/malloc_tuning.py
+++ b/src/malloc_tuning.py
@@ -117,6 +117,12 @@ class MallocTrimmer:
             logger.debug("malloc_trim failed; not trying again", exc_info=True)
             self._libc = None
             return False
-        logger.debug("malloc_trim(0) took %.1f ms, released=%s",
-                     (self._clock() - now) * 1000.0, released)
+        def _rss():
+            try:
+                with open('/proc/self/statm') as f:
+                    return int(f.read().split()[1]) * 4096 // 1024
+            except Exception:
+                return -1
+        logger.info("EXP malloc_trim(0) took %.1f ms, released=%s rss_kb_after=%d",
+                     (self._clock() - now) * 1000.0, released, _rss())
         return released