diff --git a/contrib/fuzz/dirs.cc b/contrib/fuzz/dirs.cc
--- a/contrib/fuzz/dirs.cc
+++ b/contrib/fuzz/dirs.cc
@@ -35,9 +35,10 @@
 
 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
 {
-	// Don't allow fuzzer inputs larger than 100k, since we'll just bog
-	// down and not accomplish much.
-	if (Size > 100000) {
+	// Don't allow fuzzer inputs larger than 40k: the fuzzer will
+	// discover that if it passes us one extremely long path we'll
+	// use a ton of RAM, which is a surprise to nobody.
+	if (Size > 40000) {
 		return 0;
 	}
 	PyObject *mtext =