Tracking System Calls
When you want to know what a process is doing, you can track all system calls of a process using the strace command.
- Running
php start.php statuswill display information about the Workerman-related processes as follows:
Hello admin
---------------------------------------GLOBAL STATUS--------------------------------------------
Workerman version:3.0.1
start time:2014-08-12 17:42:04 run 0 days 1 hours
load average: 3.34, 3.59, 3.67
1 users 8 workers 14 processes
worker_name exit_status exit_count
BusinessWorker 0 0
ChatWeb 0 0
FileMonitor 0 0
Gateway 0 0
Monitor 0 0
StatisticProvider 0 0
StatisticWeb 0 0
StatisticWorker 0 0
---------------------------------------PROCESS STATUS-------------------------------------------
pid memory listening timestamp worker_name total_request packet_err thunder_herd client_close send_fail throw_exception suc/total
10352 1.5M tcp://0.0.0.0:55151 1407836524 ChatWeb 12 0 0 2 0 0 100%
10354 1.25M tcp://0.0.0.0:7272 1407836524 Gateway 3 0 0 0 0 0 100%
10355 1.25M tcp://0.0.0.0:7272 1407836524 Gateway 0 0 1 0 0 0 100%
10365 1.25M tcp://0.0.0.0:55757 1407836524 StatisticWeb 0 0 0 0 0 0 100%
10358 1.25M tcp://0.0.0.0:7272 1407836524 Gateway 3 0 2 0 0 0 100%
10364 1.25M tcp://0.0.0.0:55858 1407836524 StatisticProvider 0 0 0 0 0 0 100%
10356 1.25M tcp://0.0.0.0:7272 1407836524 Gateway 3 0 2 0 0 0 100%
10366 1.25M udp://0.0.0.0:55656 1407836524 StatisticWorker 55 0 0 0 0 0 100%
10349 1.25M tcp://127.0.0.1:7373 1407836524 BusinessWorker 5 0 0 0 0 0 100%
10350 1.25M tcp://127.0.0.1:7373 1407836524 BusinessWorker 0 0 0 0 0 0 100%
10351 1.5M tcp://127.0.0.1:7373 1407836524 BusinessWorker 5 0 0 0 0 0 100%
10348 1.25M tcp://127.0.0.1:7373 1407836524 BusinessWorker 2 0 0 0 0 0 100%- For example, if we want to know what the gateway process with PID 10354 is doing, we can run the command
strace -p 10354(may require root privileges) as shown below:
sudo strace -p 10354
Process 10354 attached - interrupt to quit
clock_gettime(CLOCK_MONOTONIC, {118627, 242986712}) = 0
gettimeofday({1407840609, 102439}, NULL) = 0
epoll_wait(3, 985f4f0, 32, -1) = -1 EINTR (Interrupted system call)
--- SIGUSR2 (User defined signal 2) @ 0 (0) ---
send(7, "\f", 1, 0) = 1
sigreturn() = ? (mask now [])
clock_gettime(CLOCK_MONOTONIC, {118627, 699623319}) = 0
gettimeofday({1407840609, 559092}, NULL) = 0
epoll_wait(3, {{EPOLLIN, {u32=9, u64=9}}}, 32, -1) = 1
clock_gettime(CLOCK_MONOTONIC, {118627, 699810499}) = 0
gettimeofday({1407840609, 559277}, NULL) = 0
recv(9, "\f", 1024, 0) = 1
recv(9, 0xb60b4880, 1024, 0) = -1 EAGAIN (Resource temporarily unavailable)
epoll_wait(3, 985f4f0, 32, -1) = -1 EINTR (Interrupted system call)
--- SIGUSR2 (User defined signal 2) @ 0 (0) ---
send(7, "\f", 1, 0) = 1
sigreturn() = ? (mask now [])
clock_gettime(CLOCK_MONOTONIC, {118628, 699497204}) = 0
gettimeofday({1407840610, 558937}, NULL) = 0
epoll_wait(3, {{EPOLLIN, {u32=9, u64=9}}}, 32, -1) = 1
clock_gettime(CLOCK_MONOTONIC, {118628, 699588603}) = 0
gettimeofday({1407840610, 559023}, NULL) = 0
recv(9, "\f", 1024, 0) = 1
recv(9, 0xb60b4880, 1024, 0) = -1 EAGAIN (Resource temporarily unavailable)
epoll_wait(3, 985f4f0, 32, -1) = -1 EINTR (Interrupted system call)
--- SIGUSR2 (User defined signal 2) @ 0 (0) ---
send(7, "\f", 1, 0) = 1
sigreturn() = ? (mask now [])- Each line represents a system call, and from this information, we can easily see what the process is doing. It allows us to locate where the process is stuck, whether it's in connection or reading network data, etc.