diff --git a/media/libmediaplayerservice/StagefrightRecorder.cpp b/media/libmediaplayerservice/StagefrightRecorder.cpp
index ec3b5a2..d2dbf0d 100644
--- a/media/libmediaplayerservice/StagefrightRecorder.cpp
+++ b/media/libmediaplayerservice/StagefrightRecorder.cpp
@@ -366,6 +366,9 @@
         return BAD_VALUE;
     }
 
+    if (timeUs <= 15 * 1000000LL) {
+        LOGW("Target duration (%lld us) too short to be respected", timeUs);
+    }
     mMaxFileDurationUs = timeUs;
     return OK;
 }
@@ -376,6 +379,11 @@
         LOGE("Max file size is too small: %lld bytes", bytes);
         return BAD_VALUE;
     }
+
+    if (bytes <= 100 * 1024) {
+        LOGW("Target file size (%lld bytes) is too small to be respected", bytes);
+    }
+
     mMaxFileSizeBytes = bytes;
     return OK;
 }
diff --git a/media/libstagefright/MPEG4Writer.cpp b/media/libstagefright/MPEG4Writer.cpp
index 6760707..602aa9f 100644
--- a/media/libstagefright/MPEG4Writer.cpp
+++ b/media/libstagefright/MPEG4Writer.cpp
@@ -878,7 +878,10 @@
         nTotalBytesEstimate += (*it)->getEstimatedTrackSizeBytes();
     }
 
-    return (nTotalBytesEstimate >= mMaxFileSizeLimitBytes);
+    // Be conservative in the estimate: do not exceed 95% of
+    // the target file limit. For small target file size limit, though,
+    // this will not help.
+    return (nTotalBytesEstimate >= (95 * mMaxFileSizeLimitBytes) / 100);
 }
 
 bool MPEG4Writer::exceedsFileDurationLimit() {