diff --git a/test/nested.cc b/test/nested.cc
index 45ffbc47..d90eae90 100644
--- a/test/nested.cc
+++ b/test/nested.cc
@@ -209,7 +209,10 @@ retry:
 
     if (unlikely(!keyvalue_maker.increment(serial, 1))) {
       log_notice("nested: unexpected key-space overflow");
-      return false;
+      keyspace_overflow = true;
+      head_count = n;
+      stochastic_breakable_restart_with_nested(true);
+      goto retry;
     }
   }
 
@@ -278,8 +281,8 @@ bool testcase_nested::run() {
       return false;
     }
 
-    if (should_continue() || !clear_wholetable_passed ||
-        !clear_stepbystep_passed) {
+    if (!keyspace_overflow && (should_continue() || !clear_wholetable_passed ||
+                               !clear_stepbystep_passed)) {
       unsigned underutilization_x256 =
           txn_underutilization_x256(txn_guard.get());
       if (dbfull_passed > underutilization_x256) {
diff --git a/test/test.h b/test/test.h
index 2399ee58..f9afb450 100644
--- a/test/test.h
+++ b/test/test.h
@@ -301,6 +301,7 @@ class testcase_nested : public testcase {
   unsigned clear_wholetable_passed{0};
   unsigned clear_stepbystep_passed{0};
   unsigned dbfull_passed{0};
+  bool keyspace_overflow{false};
   FIFO fifo;
   std::stack<std::tuple<scoped_txn_guard, uint64_t, FIFO, SET>> stack;
 
diff --git a/test/ttl.cc b/test/ttl.cc
index 428a90c2..d095c9f6 100644
--- a/test/ttl.cc
+++ b/test/ttl.cc
@@ -81,6 +81,7 @@ bool testcase_ttl::run() {
   unsigned clear_stepbystep_passed = 0;
   unsigned dbfull_passed = 0;
   unsigned loops = 0;
+  bool keyspace_overflow = false;
   while (true) {
     const uint64_t salt = prng64_white(seed) /* mdbx_txn_id(txn_guard.get()) */;
 
@@ -134,8 +135,8 @@ bool testcase_ttl::run() {
       return false;
     }
 
-    if (should_continue() || !clear_wholetable_passed ||
-        !clear_stepbystep_passed) {
+    if (!keyspace_overflow && (should_continue() || !clear_wholetable_passed ||
+                               !clear_stepbystep_passed)) {
       unsigned underutilization_x256 =
           txn_underutilization_x256(txn_guard.get());
       if (dbfull_passed > underutilization_x256) {
@@ -165,7 +166,11 @@ bool testcase_ttl::run() {
 
         if (unlikely(!keyvalue_maker.increment(serial, 1))) {
           log_notice("ttl: unexpected key-space overflow");
-          goto bailout;
+          keyspace_overflow = true;
+          txn_restart(true, false);
+          serial = fifo.front().first;
+          fifo.front().second = head_count = n;
+          goto retry;
         }
       }
       err = breakable_restart();