why apisix test in t/ always show timeout when waiting for the process?

[xuminwlt]

case 1:

prove -I. -I../test-nginx/inc -I../test-nginx/lib -r t/admin/api.t      
 t/admin/api.t .. 1/? t/admin/api.t TEST 2: Server header for admin API without token - timeout when waiting for the process 59744 to exit at /Users/xxx/Documents/IdeaProjects/github/apisix/../test-nginx/lib/Test/Nginx/Util.pm line 657. 
 t/admin/api.t .. 5/? END - timeout when waiting for the process 59764 to exit at /Users/xxx/Documents/IdeaProjects/github/apisix/../test-nginx/lib/Test/Nginx/Util.pm line 657. 
 t/admin/api.t .. ok    All tests successful. Files=1, Tests=8,  7 wallclock secs ( 0.03 usr  0.01 sys +  0.22 cusr  0.10 csys =  0.36 CPU) Result: PASS

case 2:

prove -I. -I../test-nginx/inc -I../test-nginx/lib -r t/plugin/opa.t 
t/plugin/opa.t .. 1/? t/plugin/opa.t TEST 2: setup route with plugin - timeout when waiting for the process 60087 to exit at /Users/xxx/Documents/IdeaProjects/github/apisix/../test-nginx/lib/Test/Nginx/Util.pm line 657.
t/plugin/opa.t .. 4/? t/plugin/opa.t TEST 3: hit route (with correct request) - timeout when waiting for the process 60113 to exit at /Users/xxx/Documents/IdeaProjects/github/apisix/../test-nginx/lib/Test/Nginx/Util.pm line 657.
t/plugin/opa.t .. 7/? 
#   Failed test 't/plugin/opa.t TEST 3: hit route (with correct request) - status code ok'
#   at /Users/xxx/Documents/IdeaProjects/github/apisix/../test-nginx/lib/Test/Nginx/Socket.pm line 949.

git clone from apisix, branch in master.
has make deps and test-nginx is ok.

prove -I. -I../test-nginx/inc -I../test-nginx/lib -r t/
t/apply_moves.t .......... ok   
t/check_response_body.t .. ok   
t/get_req_from_block.t ... ok   
t/learn0.t ............... ok   
t/parse_request.t ........ ok   
t/pod-coverage.t ......... skipped: we know we have poor POD coverage :P
t/pod.t .................. ok   
t/resp_body_filters.t .... ok     
t/syntax.t ............... lib/Test/Nginx/LWP.pm syntax OK
t/syntax.t ............... 1/5 lib/Test/Nginx/Socket.pm syntax OK
lib/Test/Nginx/Socket/Lua.pm syntax OK
t/syntax.t ............... 3/5 lib/Test/Nginx/Socket/Lua/Stream.pm syntax OK
lib/Test/Nginx/Socket/Lua/Dgram.pm syntax OK
t/syntax.t ............... ok   
All tests successful.
Files=9, Tests=52,  2 wallclock secs ( 0.04 usr  0.01 sys +  1.12 cusr  0.23 csys =  1.40 CPU)
Result: PASS

[xuminwlt]

got it, code in test-nginx Util.pm has described it.

if (is_running($pid)) {
                        warn "$name - timeout when waiting for the process $pid to exit";
                        kill(SIGKILL, $pid);
                        sleep 0.05;
                    }


sub is_running ($) {
    my $pid = shift;
    return kill 0, $pid;
}

[dingdinghappy]

Enter the following command to solve the problem
export TEST_NGINX_FAST_SHUTDOWN=1