diff --git a/tests/http2-server.pl b/tests/http2-server.pl
index d4367da636..8058641c17 100755
--- a/tests/http2-server.pl
+++ b/tests/http2-server.pl
@@ -108,6 +108,7 @@ $certfile = abs_path($certfile);
 $keyfile = abs_path($keyfile);
 
 my $cmdline="$nghttpx --backend=$connect ".
+    "--backend-keep-alive-timeout=500ms ".
     "--frontend=\"*,$listenport;no-tls\" ".
     "--frontend=\"*,$listenport2\" ".
     "--log-level=INFO ".
diff --git a/tests/http3-server.pl b/tests/http3-server.pl
index 97e6998be0..6c8baccb9b 100755
--- a/tests/http3-server.pl
+++ b/tests/http3-server.pl
@@ -108,6 +108,7 @@ $certfile = abs_path($certfile);
 $keyfile = abs_path($keyfile);
 
 my $cmdline="$nghttpx --http2-proxy --backend=$connect ".
+    "--backend-keep-alive-timeout=500ms ".
     "--frontend=\"*,$listenport\" ".
     "--frontend=\"*,$listenport;quic\" ".
     "--log-level=INFO ".
diff --git a/tests/runner.pm b/tests/runner.pm
index 53c98bb7ed..49aa75e54a 100644
--- a/tests/runner.pm
+++ b/tests/runner.pm
@@ -1361,6 +1361,7 @@ sub runnerar_ready {
     my $rin = "";
     my %idbyfileno;
     my $maxfileno=0;
+    my @ready_runners = ();
     foreach my $p (keys(%controllerr)) {
         my $fd = fileno($controllerr{$p});
         vec($rin, $fd, 1) = 1;
@@ -1383,10 +1384,11 @@ sub runnerar_ready {
                 return (undef, $idbyfileno{$fd});
             }
             if(vec($rout, $fd, 1)) {
-                return ($idbyfileno{$fd}, undef);
+                push(@ready_runners, $idbyfileno{$fd});
             }
         }
-        die "Internal pipe readiness inconsistency\n";
+        die "Internal pipe readiness inconsistency\n" if(!@ready_runners);
+        return (@ready_runners, undef);
     }
     return (undef, undef);
 }
diff --git a/tests/runtests.pl b/tests/runtests.pl
index b688283fb4..4221803f8a 100755
--- a/tests/runtests.pl
+++ b/tests/runtests.pl
@@ -2945,63 +2945,67 @@ while () {
     # one immediately. If all runners are busy, wait a fraction of a second
     # for one to finish so we can still loop around to check the abort flag.
     my $runnerwait = scalar(@runnersidle) && scalar(@runtests) ? 0 : 1.0;
-    my ($ridready, $riderror) = runnerar_ready($runnerwait);
-    if($ridready && ! defined $runnersrunning{$ridready}) {
-        # On Linux, a closed pipe still shows up as ready instead of error.
-        # Detect this here by seeing if we are expecting it to be ready and
-        # treat it as an error if not.
-        logmsg "ERROR: Runner $ridready is unexpectedly ready; is probably actually dead\n";
-        $riderror = $ridready;
-        undef $ridready;
-    }
-    if($ridready) {
-        # This runner is ready to be serviced
-        my $testnum = $runnersrunning{$ridready};
-        defined $testnum ||  die "Internal error: test for runner $ridready unknown";
-        delete $runnersrunning{$ridready};
-        my ($error, $again) = singletest($ridready, $testnum, $countforrunner{$ridready}, $totaltests);
-        if($again) {
-            # this runner is busy running a test
-            $runnersrunning{$ridready} = $testnum;
-        } else {
-            # Test is complete
-            $runner_wait_cnt = 0;
-            runnerready($ridready);
-
-            if($error < 0) {
-                # not a test we can run
-                next;
+    my (@ridsready, $riderror) = runnerar_ready($runnerwait);
+    if(@ridsready) {
+        for my $ridready (@ridsready) {
+            if($ridready && ! defined $runnersrunning{$ridready}) {
+                # On Linux, a closed pipe still shows up as ready instead of error.
+                # Detect this here by seeing if we are expecting it to be ready and
+                # treat it as an error if not.
+                logmsg "ERROR: Runner $ridready is unexpectedly ready; is probably actually dead\n";
+                $riderror = $ridready;
+                undef $ridready;
             }
+            if($ridready) {
+                # This runner is ready to be serviced
+                my $testnum = $runnersrunning{$ridready};
+                defined $testnum ||  die "Internal error: test for runner $ridready unknown";
+                delete $runnersrunning{$ridready};
+                my ($error, $again) = singletest($ridready, $testnum, $countforrunner{$ridready}, $totaltests);
+                if($again) {
+                    # this runner is busy running a test
+                    $runnersrunning{$ridready} = $testnum;
+                } else {
+                    # Test is complete
+                    $runner_wait_cnt = 0;
+                    runnerready($ridready);
 
-            $total++; # number of tests we've run
+                    if($error < 0) {
+                        # not a test we can run
+                        next;
+                    }
 
-            if($error>0) {
-                if($error==2) {
-                    # ignored test failures
-                    $failedign .= "$testnum ";
+                    $total++; # number of tests we've run
+
+                    if($error>0) {
+                        if($error==2) {
+                            # ignored test failures
+                            $failedign .= "$testnum ";
+                        }
+                        else {
+                            $failed.= "$testnum ";
+                        }
+                        if($postmortem) {
+                            # display all files in $LOGDIR/ in a nice way
+                            displaylogs($ridready, $testnum);
+                        }
+                        if($error==2) {
+                            $ign++; # ignored test result counter
+                        }
+                        elsif(!$anyway) {
+                            # a test failed, abort
+                            logmsg "\n - abort tests\n";
+                            undef @runtests;  # empty out the remaining tests
+                        }
+                    }
+                    elsif(!$error) {
+                        $ok++; # successful test counter
+                    }
                 }
-                else {
-                    $failed.= "$testnum ";
-                }
-                if($postmortem) {
-                    # display all files in $LOGDIR/ in a nice way
-                    displaylogs($ridready, $testnum);
-                }
-                if($error==2) {
-                    $ign++; # ignored test result counter
-                }
-                elsif(!$anyway) {
-                    # a test failed, abort
-                    logmsg "\n - abort tests\n";
-                    undef @runtests;  # empty out the remaining tests
-                }
-            }
-            elsif(!$error) {
-                $ok++; # successful test counter
             }
         }
     }
-    if(!$ridready && $runnerwait && !$torture && scalar(%runnersrunning)) {
+    if(!@ridsready && $runnerwait && !$torture && scalar(%runnersrunning)) {
         $runner_wait_cnt++;
         if($runner_wait_cnt >= 5) {
             my $msg = "waiting for " . scalar(%runnersrunning) . " results:";