diff --git a/t/023-rewrite/uthread-exit.t b/t/023-rewrite/uthread-exit.t
index 87f850ce8b..ec0ce4534f 100644
--- a/t/023-rewrite/uthread-exit.t
+++ b/t/023-rewrite/uthread-exit.t
@@ -8,7 +8,7 @@ our $StapScript = $t::StapThread::StapScript;
 
 repeat_each(2);
 
-plan tests => repeat_each() * (blocks() * 4 + 1);
+plan tests => repeat_each() * (blocks() * 4);
 
 $ENV{TEST_NGINX_RESOLVER} ||= '8.8.8.8';
 $ENV{TEST_NGINX_MEMCACHED_PORT} ||= '11211';
@@ -299,7 +299,7 @@ exiting the user thread
 --- config
     location /lua {
         resolver 127.0.0.2:12345;
-        resolver_timeout 12s;
+        resolver_timeout 2s;
         rewrite_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -321,82 +321,13 @@ exiting the user thread
     }
 --- request
 GET /lua
---- stap2 eval: $::StapScript
---- stap eval
-<<'_EOC_' . $::GCScript;
-
-global timers
-
-F(ngx_resolve_start) {
-    println("resolver started")
-}
-
-F(ngx_http_lua_socket_resolve_handler) {
-    println("resolver done")
-}
-
-F(ngx_http_free_request) {
-    println("free request")
-}
-
-F(ngx_resolve_name) {
-    printf("resolving %s\n", user_string_n($ctx->name->data, $ctx->name->len))
-}
-
-M(timer-add) {
-    if ($arg2 == 12000 || $arg2 == 1) {
-        timers[$arg1] = $arg2
-        printf("add timer %d\n", $arg2)
-    }
-}
-
-M(timer-del) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 1) {
-        printf("delete timer %d\n", tm)
-        delete timers[$arg1]
-    }
-    /*
-    if (tm == 12000) {
-        print_ubacktrace()
-    }
-    */
-}
-
-M(timer-expire) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 1) {
-        printf("expire timer %d\n", timers[$arg1])
-        delete timers[$arg1]
-    }
-}
-
-F(ngx_http_lua_tcp_resolve_cleanup) {
-    println("lua tcp resolve cleanup")
-}
-_EOC_
-
---- stap_out
-create 2 in 1
-spawn user thread 2 in 1
-add timer 1
-resolver started
-resolving agentzh.org
-add timer 12000
-expire timer 1
-terminate 2: ok
-delete thread 2
-lua tcp resolve cleanup
-delete timer 12000
-delete thread 1
-free request
-
 --- response_body
 before
 hello in thread
 after
 --- no_error_log
 [error]
+[crit]
 
 
 
@@ -405,8 +336,9 @@ after
     location /lua {
         resolver 127.0.0.2:12345;
         #resolver 127.0.0.1;
-        resolver_timeout 12s;
+        resolver_timeout 2s;
         rewrite_by_lua '
+            collectgarbage("collect")
             local function f()
                 ngx.say("hello in thread")
                 ngx.sleep(0.001)
@@ -427,76 +359,6 @@ after
     }
 --- request
 GET /lua
---- stap2 eval: $::StapScript
---- stap eval
-<<'_EOC_' . $::GCScript;
-
-global timers
-
-F(ngx_resolve_start) {
-    println("resolver started")
-}
-
-F(ngx_http_lua_socket_resolve_handler) {
-    println("resolver done")
-}
-
-F(ngx_http_free_request) {
-    println("free request")
-}
-
-F(ngx_resolve_name) {
-    printf("resolving %s\n", user_string_n($ctx->name->data, $ctx->name->len))
-}
-
-M(timer-add) {
-    if ($arg2 == 12000 || $arg2 == 1) {
-        timers[$arg1] = $arg2
-        printf("add timer %d\n", $arg2)
-    }
-}
-
-M(timer-del) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 1) {
-        printf("delete timer %d\n", tm)
-        delete timers[$arg1]
-    }
-    /*
-    if (tm == 12000) {
-        print_ubacktrace()
-    }
-    */
-}
-
-M(timer-expire) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 1) {
-        printf("expire timer %d\n", timers[$arg1])
-        delete timers[$arg1]
-    }
-}
-
-F(ngx_http_lua_udp_resolve_cleanup) {
-    println("lua udp resolve cleanup")
-}
-_EOC_
-
---- stap_out
-create 2 in 1
-spawn user thread 2 in 1
-add timer 1
-resolver started
-resolving agentzh.org
-add timer 12000
-expire timer 1
-terminate 2: ok
-delete thread 2
-lua udp resolve cleanup
-delete timer 12000
-delete thread 1
-free request
-
 --- response_body
 before
 hello in thread
@@ -994,7 +856,7 @@ after
 === TEST 12: exit in user thread (entry thread is still pending on ngx.req.read_body)
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         rewrite_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -1080,7 +942,7 @@ after
 === TEST 13: exit in user thread (entry thread is still pending on ngx.location.capture), with pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         rewrite_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -1164,7 +1026,7 @@ attempt to abort with pending subrequests
 === TEST 14: exit in user thread (entry thread is still pending on ngx.location.capture), without pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         rewrite_by_lua '
             local function f()
                 ngx.sleep(0.1)
@@ -1247,7 +1109,7 @@ attempt to abort with pending subrequests
 === TEST 15: exit in user thread (entry thread is still pending on ngx.location.capture_multi), without pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         rewrite_by_lua '
             local function f()
                 ngx.sleep(0.1)
diff --git a/t/024-access/uthread-exit.t b/t/024-access/uthread-exit.t
index bd165ae708..0ee5fbab82 100644
--- a/t/024-access/uthread-exit.t
+++ b/t/024-access/uthread-exit.t
@@ -299,7 +299,7 @@ exiting the user thread
 --- config
     location /lua {
         resolver 127.0.0.2:12345;
-        resolver_timeout 12s;
+        resolver_timeout 2s;
         access_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -321,73 +321,13 @@ exiting the user thread
     }
 --- request
 GET /lua
---- stap2 eval: $::StapScript
---- stap eval
-<<'_EOC_' . $::GCScript;
-
-global timers
-
-F(ngx_http_free_request) {
-    println("free request")
-}
-
-F(ngx_resolve_name) {
-    printf("resolving %s\n", user_string_n($ctx->name->data, $ctx->name->len))
-}
-
-M(timer-add) {
-    if ($arg2 == 12000 || $arg2 == 1) {
-        timers[$arg1] = $arg2
-        printf("add timer %d\n", $arg2)
-    }
-}
-
-M(timer-del) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 1) {
-        printf("delete timer %d\n", tm)
-        delete timers[$arg1]
-    }
-    /*
-    if (tm == 12000) {
-        print_ubacktrace()
-    }
-    */
-}
-
-M(timer-expire) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 1) {
-        printf("expire timer %d\n", timers[$arg1])
-        delete timers[$arg1]
-    }
-}
-
-F(ngx_http_lua_tcp_resolve_cleanup) {
-    println("lua tcp resolve cleanup")
-}
-_EOC_
-
---- stap_out
-create 2 in 1
-spawn user thread 2 in 1
-add timer 1
-resolving agentzh.org
-add timer 12000
-expire timer 1
-terminate 2: ok
-delete thread 2
-lua tcp resolve cleanup
-delete timer 12000
-delete thread 1
-free request
-
 --- response_body
 before
 hello in thread
 after
 --- no_error_log
 [error]
+[crit]
 
 
 
@@ -395,7 +335,7 @@ after
 --- config
     location /lua {
         resolver 127.0.0.2:12345;
-        resolver_timeout 12s;
+        resolver_timeout 2s;
         access_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -417,73 +357,13 @@ after
     }
 --- request
 GET /lua
---- stap2 eval: $::StapScript
---- stap eval
-<<'_EOC_' . $::GCScript;
-
-global timers
-
-F(ngx_http_free_request) {
-    println("free request")
-}
-
-F(ngx_resolve_name) {
-    printf("resolving %s\n", user_string_n($ctx->name->data, $ctx->name->len))
-}
-
-M(timer-add) {
-    if ($arg2 == 12000 || $arg2 == 1) {
-        timers[$arg1] = $arg2
-        printf("add timer %d\n", $arg2)
-    }
-}
-
-M(timer-del) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 1) {
-        printf("delete timer %d\n", tm)
-        delete timers[$arg1]
-    }
-    /*
-    if (tm == 12000) {
-        print_ubacktrace()
-    }
-    */
-}
-
-M(timer-expire) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 1) {
-        printf("expire timer %d\n", timers[$arg1])
-        delete timers[$arg1]
-    }
-}
-
-F(ngx_http_lua_udp_resolve_cleanup) {
-    println("lua udp resolve cleanup")
-}
-_EOC_
-
---- stap_out
-create 2 in 1
-spawn user thread 2 in 1
-add timer 1
-resolving agentzh.org
-add timer 12000
-expire timer 1
-terminate 2: ok
-delete thread 2
-lua udp resolve cleanup
-delete timer 12000
-delete thread 1
-free request
-
 --- response_body
 before
 hello in thread
 after
 --- no_error_log
 [error]
+[crit]
 
 
 
@@ -977,7 +857,7 @@ after
 --- skip_eval: 3:$ENV{TEST_NGINX_USE_HTTP3}
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         access_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -998,57 +878,6 @@ after
 POST /lua
 --- more_headers
 Content-Length: 1024
---- stap2 eval: $::StapScript
---- stap eval
-<<'_EOC_' . $::GCScript;
-
-global timers
-
-F(ngx_http_free_request) {
-    println("free request")
-}
-
-M(timer-add) {
-    if ($arg2 == 12000 || $arg2 == 100) {
-        timers[$arg1] = $arg2
-        printf("add timer %d\n", $arg2)
-    }
-}
-
-M(timer-del) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 100) {
-        printf("delete timer %d\n", tm)
-        delete timers[$arg1]
-    }
-}
-
-M(timer-expire) {
-    tm = timers[$arg1]
-    if (tm == 12000 || tm == 100) {
-        printf("expire timer %d\n", timers[$arg1])
-        delete timers[$arg1]
-    }
-}
-
-F(ngx_http_lua_req_body_cleanup) {
-    println("lua req body cleanup")
-}
-_EOC_
-
---- stap_out
-create 2 in 1
-spawn user thread 2 in 1
-add timer 100
-add timer 12000
-expire timer 100
-terminate 2: ok
-delete thread 2
-lua req body cleanup
-delete timer 12000
-delete thread 1
-free request
-
 --- wait: 0.1
 --- response_body
 before
@@ -1056,13 +885,14 @@ hello in thread
 after
 --- no_error_log
 [error]
+[crit]
 
 
 
 === TEST 13: exit in user thread (entry thread is still pending on ngx.location.capture), with pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         access_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -1085,53 +915,6 @@ after
     }
 --- request
 POST /lua
---- stap2 eval: $::StapScript
---- stap eval
-<<'_EOC_' . $::GCScript;
-
-global timers
-
-F(ngx_http_free_request) {
-    println("free request")
-}
-
-M(timer-add) {
-    if ($arg2 == 200 || $arg2 == 100) {
-        timers[$arg1] = $arg2
-        printf("add timer %d\n", $arg2)
-    }
-}
-
-M(timer-del) {
-    tm = timers[$arg1]
-    if (tm == 200 || tm == 100) {
-        printf("delete timer %d\n", tm)
-        delete timers[$arg1]
-    }
-}
-
-M(timer-expire) {
-    tm = timers[$arg1]
-    if (tm == 200 || tm == 100) {
-        printf("expire timer %d\n", timers[$arg1])
-        delete timers[$arg1]
-    }
-}
-_EOC_
-
---- stap_out
-create 2 in 1
-spawn user thread 2 in 1
-add timer 100
-add timer 200
-expire timer 100
-terminate 2: fail
-expire timer 200
-terminate 1: ok
-delete thread 2
-delete thread 1
-free request
-
 --- wait: 0.1
 --- response_body
 before
@@ -1140,13 +923,15 @@ after
 end
 --- error_log
 attempt to abort with pending subrequests
+--- no_error_log
+[crit]
 
 
 
 === TEST 14: exit in user thread (entry thread is still pending on ngx.location.capture), without pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         access_by_lua '
             local function f()
                 ngx.sleep(0.1)
@@ -1165,71 +950,20 @@ attempt to abort with pending subrequests
     }
 --- request
 POST /lua
---- stap2 eval: $::StapScript
---- stap eval
-<<'_EOC_' . $::GCScript;
-
-global timers
-
-F(ngx_http_free_request) {
-    println("free request")
-}
-
-M(timer-add) {
-    if ($arg2 == 200 || $arg2 == 100) {
-        timers[$arg1] = $arg2
-        printf("add timer %d\n", $arg2)
-    }
-}
-
-M(timer-del) {
-    tm = timers[$arg1]
-    if (tm == 200 || tm == 100) {
-        printf("delete timer %d\n", tm)
-        delete timers[$arg1]
-    }
-}
-
-M(timer-expire) {
-    tm = timers[$arg1]
-    if (tm == 200 || tm == 100) {
-        printf("expire timer %d\n", timers[$arg1])
-        delete timers[$arg1]
-    }
-}
-
-F(ngx_http_lua_post_subrequest) {
-    printf("post subreq %s\n", ngx_http_req_uri($r))
-}
-
-_EOC_
-
---- stap_out
-create 2 in 1
-spawn user thread 2 in 1
-add timer 100
-add timer 200
-expire timer 100
-terminate 2: fail
-expire timer 200
-post subreq /sleep
-terminate 1: ok
-delete thread 2
-delete thread 1
-free request
-
 --- wait: 0.1
 --- response_body
 end
 --- error_log
 attempt to abort with pending subrequests
+--- no_error_log
+[crit]
 
 
 
 === TEST 15: exit in user thread (entry thread is still pending on ngx.location.capture_multi), without pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         access_by_lua '
             local function f()
                 ngx.sleep(0.1)
@@ -1255,61 +989,10 @@ attempt to abort with pending subrequests
     }
 --- request
 POST /lua
---- stap2 eval: $::StapScript
---- stap eval
-<<'_EOC_' . $::GCScript;
-
-global timers
-
-F(ngx_http_free_request) {
-    println("free request")
-}
-
-M(timer-add) {
-    if ($arg2 == 200 || $arg2 == 100) {
-        timers[$arg1] = $arg2
-        printf("add timer %d\n", $arg2)
-    }
-}
-
-M(timer-del) {
-    tm = timers[$arg1]
-    if (tm == 200 || tm == 100) {
-        printf("delete timer %d\n", tm)
-        delete timers[$arg1]
-    }
-}
-
-M(timer-expire) {
-    tm = timers[$arg1]
-    if (tm == 200 || tm == 100) {
-        printf("expire timer %d\n", timers[$arg1])
-        delete timers[$arg1]
-    }
-}
-
-F(ngx_http_lua_post_subrequest) {
-    printf("post subreq %s\n", ngx_http_req_uri($r))
-}
-_EOC_
-
---- stap_out
-create 2 in 1
-spawn user thread 2 in 1
-add timer 100
-post subreq /echo
-add timer 200
-expire timer 100
-terminate 2: fail
-expire timer 200
-post subreq /sleep
-terminate 1: ok
-delete thread 2
-delete thread 1
-free request
-
 --- wait: 0.1
 --- response_body
 end
 --- error_log
 attempt to abort with pending subrequests
+--- no_error_log
+[crit]
diff --git a/t/039-sub-o.t b/t/039-sub-o.t
index 580a67161e..5cdba6b5ee 100644
--- a/t/039-sub-o.t
+++ b/t/039-sub-o.t
@@ -8,7 +8,7 @@ use Test::Nginx::Socket::Lua;
 
 repeat_each(2);
 
-plan tests => repeat_each() * (blocks() * 2 + 6);
+plan 'no_plan';
 
 #no_diff();
 no_long_string();
@@ -54,6 +54,7 @@ hello, world
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect") -- memory leak test
             local s, n = ngx.re.sub("a b c d", "(b) (c)", "[$0] [$1] [$2] [$3] [$134]", "o")
             ngx.say(s)
             ngx.say(n)
@@ -71,6 +72,7 @@ a [b c] [b] [c] [] [] d
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect") -- memory leak test
             local s, n, err = ngx.re.sub("a b c d",
                                          "(b) (c)",
                                          "[$0] [$1] [$2] [$3] [$hello]",
@@ -96,6 +98,7 @@ attempt to use named capturing variable "hello" (named captures not supported ye
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect") -- memory leak test
             local s, n, err = ngx.re.sub("a b c d",
                                          "(b) (c)",
                                          "[$0] [$1] [$2] [$3] [${hello}]",
@@ -120,6 +123,7 @@ attempt to use named capturing variable "hello" (named captures not supported ye
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect") -- memory leak test
             local s, n = ngx.re.sub("b c d", "(b) (c)", "[$0] [$1] [${2}] [$3] [${134}]", "o")
             ngx.say(s)
             ngx.say(n)
@@ -137,6 +141,7 @@ attempt to use named capturing variable "hello" (named captures not supported ye
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect") -- memory leak test
             local s, n, err = ngx.re.sub("b c d", "(b) (c)", "[$0] [$1] [${2}] [$3] [${134]", "o")
             if s then
                 ngx.say(s, ": ", n)
@@ -158,6 +163,7 @@ the closing bracket in "134" variable is missing
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect") -- memory leak test
             local s, n, err = ngx.re.sub("b c d", "(b) (c)", "[$0] [$1] [${2}] [$3] [${134", "o")
             if s then
                 ngx.say(s, ": ", n)
@@ -179,6 +185,7 @@ the closing bracket in "134" variable is missing
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect") -- memory leak test
             local s, n, err = ngx.re.sub("b c d", "(b) (c)", "[$0] [$1] [${2}] [$3] [${", "o")
             if s then
                 ngx.say(s, ": ", n)
@@ -200,6 +207,7 @@ lua script: invalid capturing variable name found in "[$0] [$1] [${2}] [$3] [${"
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect") -- memory leak test
             local s, n, err = ngx.re.sub("b c d", "(b) (c)", "[$0] [$1] [${2}] [$3] [$", "o")
             if s then
                 ngx.say(s, ": ", n)
diff --git a/t/094-uthread-exit.t b/t/094-uthread-exit.t
index 375d8d6023..62f4c5bbca 100644
--- a/t/094-uthread-exit.t
+++ b/t/094-uthread-exit.t
@@ -8,7 +8,7 @@ our $StapScript = $t::StapThread::StapScript;
 
 repeat_each(2);
 
-plan tests => repeat_each() * (blocks() * 4 - 2);
+plan 'no_plan';
 
 $ENV{TEST_NGINX_RESOLVER} ||= '8.8.8.8';
 $ENV{TEST_NGINX_MEMCACHED_PORT} ||= '11211';
@@ -298,7 +298,7 @@ exiting the user thread
 --- config
     location /lua {
         resolver 127.0.0.2:12345;
-        resolver_timeout 12s;
+        resolver_timeout 2s;
         content_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -394,7 +394,7 @@ after
 --- config
     location /lua {
         resolver 127.0.0.2:12345;
-        resolver_timeout 12s;
+        resolver_timeout 2s;
         content_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -973,7 +973,7 @@ after
 === TEST 12: exit in user thread (entry thread is still pending on ngx.req.read_body)
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         content_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -1059,7 +1059,7 @@ after
 === TEST 13: exit(0) in user thread (entry thread is still pending on ngx.location.capture), with pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         content_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -1141,7 +1141,7 @@ attempt to abort with pending subrequests
 === TEST 14: exit in user thread (entry thread is still pending on ngx.location.capture), without pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         content_by_lua '
             local function f()
                 ngx.sleep(0.1)
@@ -1224,7 +1224,7 @@ attempt to abort with pending subrequests
 === TEST 15: exit in user thread (entry thread is still pending on ngx.location.capture_multi), without pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         content_by_lua '
             local function f()
                 ngx.sleep(0.1)
@@ -1315,7 +1315,7 @@ attempt to abort with pending subrequests
 --- no_http2
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         content_by_lua '
             local function f()
                 ngx.location.capture_multi{
@@ -1410,7 +1410,7 @@ qr#curl: \(52\) Empty reply from server|curl: \(95\) HTTP/3 stream 0 reset by se
 --- no_http2
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         content_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -1496,7 +1496,7 @@ qr#curl: \(52\) Empty reply from server|curl: \(95\) HTTP/3 stream 0 reset by se
 --- no_http2
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         content_by_lua '
             local function f()
                 ngx.say("hello in thread")
@@ -1581,7 +1581,7 @@ qr#curl: \(52\) Empty reply from server|curl: \(95\) HTTP/3 stream 0 reset by se
 === TEST 19: exit(499) in user thread (entry thread is still pending on ngx.location.capture), with pending output
 --- config
     location /lua {
-        client_body_timeout 12000ms;
+        client_body_timeout 2000ms;
         content_by_lua '
             local function f()
                 ngx.say("hello in thread")
diff --git a/t/120-re-find.t b/t/120-re-find.t
index 43ccece1ab..70c64e9469 100644
--- a/t/120-re-find.t
+++ b/t/120-re-find.t
@@ -9,7 +9,7 @@ use Test::Nginx::Socket::Lua;
 
 repeat_each(2);
 
-plan tests => repeat_each() * (blocks() * 3 + 1);
+plan 'no_plan';
 
 #no_diff();
 no_long_string();
@@ -33,6 +33,7 @@ __DATA__
                 end
                 ngx.say("not matched!")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -62,6 +63,7 @@ matched: 1234
                 end
                 ngx.say("not matched!")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -88,6 +90,7 @@ matched:
             else
                 ngx.say("not matched!")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -115,6 +118,7 @@ matched: hello, 1234
             else
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -136,6 +140,7 @@ not matched.
             else
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -161,6 +166,7 @@ not matched.
             else
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -186,6 +192,7 @@ matched: hello
             end
 
             ngx.say(string.sub(s, from, to))
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -211,6 +218,7 @@ matched: hello
             else
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -238,6 +246,7 @@ matched: world
             else
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -265,6 +274,7 @@ matched: hello
             else
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -290,6 +300,7 @@ not matched.
             else
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -318,6 +329,7 @@ world
             else
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -335,6 +347,7 @@ matched: he
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect")
             local s = "hello\\nworld"
             local from, to, err = ngx.re.find(s, "(abc")
             if from then
@@ -383,6 +396,7 @@ $Test::Nginx::Util::PcreVersion == 2 ?
 
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -413,6 +427,7 @@ unknown flag "H"
 
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -443,6 +458,7 @@ not matched.
 
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -470,6 +486,7 @@ matched: 1234
                 ngx.say("not matched!")
                 ngx.say("pos: ", ctx.pos)
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -497,6 +514,7 @@ pos: 5
                 ngx.say("not matched!")
                 ngx.say("pos: ", ctx.pos)
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -529,6 +547,7 @@ pos: 5
 
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -561,6 +580,7 @@ matched: hello, 1234
             else
                 ngx.say("not matched")
             end
+            collectgarbage("collect")
         ';
     }
 --- request
@@ -590,6 +610,7 @@ $Test::Nginx::Util::PcreVersion == 2 ?
             else
                 ngx.say("not matched.")
             end
+            collectgarbage("collect")
         ';
     }
 --- stap
@@ -629,18 +650,13 @@ matched: 你
 >>> a.lua
 local re = [==[(?i:([\s'\"`´’‘\(\)]*)?([\d\w]+)([\s'\"`´’‘\(\)]*)?(?:=|<=>|r?like|sounds\s+like|regexp)([\s'\"`´’‘\(\)]*)?\2|([\s'\"`´’‘\(\)]*)?([\d\w]+)([\s'\"`´’‘\(\)]*)?(?:!=|<=|>=|<>|<|>|\^|is\s+not|not\s+like|not\s+regexp)([\s'\"`´’‘\(\)]*)?(?!\6)([\d\w]+))]==]
 
+collectgarbage("collect")
 local s = string.rep([[ABCDEFG]], 10)
 
 local start = ngx.now()
 
 local from, to, err = ngx.re.find(s, re, "o")
 
---[[
-ngx.update_time()
-local elapsed = ngx.now() - start
-ngx.say(elapsed, " sec elapsed.")
-]]
-
 if not from then
     if err then
         ngx.say("error: ", err)
@@ -677,18 +693,13 @@ $Test::Nginx::Util::PcreVersion == 2 ?
 >>> a.lua
 local re = [==[(?i:([\s'\"`´’‘\(\)]*)?([\d\w]+)([\s'\"`´’‘\(\)]*)?(?:=|<=>|r?like|sounds\s+like|regexp)([\s'\"`´’‘\(\)]*)?\2|([\s'\"`´’‘\(\)]*)?([\d\w]+)([\s'\"`´’‘\(\)]*)?(?:!=|<=|>=|<>|<|>|\^|is\s+not|not\s+like|not\s+regexp)([\s'\"`´’‘\(\)]*)?(?!\6)([\d\w]+))]==]
 
+collectgarbage("collect")
 local s = string.rep([[ABCDEFG]], 10)
 
 local start = ngx.now()
 
 local from, to, err = ngx.re.find(s, re, "o")
 
---[[
-ngx.update_time()
-local elapsed = ngx.now() - start
-ngx.say(elapsed, " sec elapsed.")
-]]
-
 if not from then
     if err then
         ngx.say("error: ", err)
@@ -712,6 +723,7 @@ failed to match
     location /re {
         content_by_lua '
             local s = "hello, 1234"
+            collectgarbage("collect")
             local from, to, err = ngx.re.find(s, "([0-9])([0-9]+)", "jo", nil, 1)
             if from then
                 ngx.say("from: ", from)
@@ -740,6 +752,7 @@ matched: 1
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect")
             local s = "hello, 1234"
             local from, to, err = ngx.re.find(s, "([0-9])([0-9]+)", "jo", nil, 0)
             if from then
@@ -769,6 +782,7 @@ matched: 1234
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect")
             local s = "hello, 1234"
             local from, to, err = ngx.re.find(s, "([0-9])([0-9]+)", "jo", nil, 2)
             if from then
@@ -798,6 +812,7 @@ matched: 234
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect")
             local s = "hello, 1234"
             local from, to, err = ngx.re.find(s, "([0-9])([0-9]+)", "jo", nil, 3)
             if from then
@@ -826,6 +841,7 @@ error: nth out of bound
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect")
             local s = "hello, 1234"
             local from, to, err = ngx.re.find(s, "([0-9])([0-9]+)", "jo", nil, 4)
             if from then
@@ -854,6 +870,7 @@ error: nth out of bound
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect")
             local s = "hello, 1234"
             local from, to, err = ngx.re.find(s, "([0-9])|(hello world)", "jo", nil, 2)
             if from or to then
@@ -882,6 +899,7 @@ not matched!
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect")
             local s = "hello, 1234"
             local from, to, err = ngx.re.find(s, "(hello world)|([0-9])", "jo", nil, 1)
             if from or to then
@@ -910,6 +928,7 @@ not matched!
 --- config
     location /re {
         content_by_lua '
+            collectgarbage("collect")
             local ctx = { pos = 3 }
             local from, to, err = ngx.re.find("1234, hello", [[(\G[0-9]+)]], "", ctx)
             if from then
@@ -939,6 +958,7 @@ pos: 5
 --- config
     location /re {
         content_by_lua_block {
+            collectgarbage("collect")
             local s = "This is <something> <something else> <something further> no more"
             local from, to, err = ngx.re.find(s, "<.*>", "d")
             if from then
diff --git a/t/127-uthread-kill.t b/t/127-uthread-kill.t
index 77cf2bf9d3..c397d433b4 100644
--- a/t/127-uthread-kill.t
+++ b/t/127-uthread-kill.t
@@ -8,7 +8,7 @@ our $StapScript = $t::StapThread::StapScript;
 
 repeat_each(2);
 
-plan tests => repeat_each() * (blocks() * 5 + 1) - 4;
+plan 'no_plan';
 
 $ENV{TEST_NGINX_RESOLVER} ||= '8.8.8.8';
 $ENV{TEST_NGINX_MEMCACHED_PORT} ||= '11211';
diff --git a/t/138-balancer.t b/t/138-balancer.t
index 0ef54f99e1..105743a679 100644
--- a/t/138-balancer.t
+++ b/t/138-balancer.t
@@ -583,6 +583,7 @@ upstream sent more data than specified in "Content-Length" header while reading
     upstream backend {
         server 127.0.0.1:$TEST_NGINX_SERVER_PORT;
         balancer_by_lua_block {
+            collectgarbage("collect") -- deal with false positive leakage test
             local ffi = require "ffi"
             local C = ffi.C
 ffi.cdef[[
diff --git a/t/143-ssl-session-fetch.t b/t/143-ssl-session-fetch.t
index 9cc1870a87..3fbb46e8f4 100644
--- a/t/143-ssl-session-fetch.t
+++ b/t/143-ssl-session-fetch.t
@@ -7,7 +7,7 @@ use File::Basename;
 
 repeat_each(3);
 
-plan tests => repeat_each() * (blocks() * 6) - 3;
+plan "no_plan";
 
 my $NginxBinary = $ENV{'TEST_NGINX_BINARY'} || 'nginx';
 my $openssl_version = eval { `$NginxBinary -V 2>&1` };