May 14, 2021 Swoole
In swoole, a related property swoole_server a file can pass
$serv->set( $array configs );
functions to configure, and these configuration options make swoole more flexible. Example:
$serv = new swoole_server("0.0.0.0", 9501);
$serv->set(array(
'worker_num' => 8,
'max_request' => 10000,
'max_conn' => 100000,
'dispatch_mode' => 2,
'debug_mode'=> 1，
'daemonize' => false,
));
The configuration options and related descriptions are as follows:
Description: Specifies the number of worker processes that are started.
Description: swoole is the master-gt; n-worker mode, the more worker processes are turned on, the greater the server load capacity, but the corresponding server will have more memory. A
t the same time, when there are too many worker processes, the overhead of switching between processes is even greater.
Therefore, it is recommended to turn on
1-4
times the number of worker processes with cpu cores.
Example:
'worker_num' => 8
Description: The maximum number of tasks allowed to be processed per worker process.
Description: When this value is set, each worker process automatically restarts max_request processing the first request.
The primary purpose of setting this value is to prevent memory overflows that can result from the worker process processing a large number of requests.
Example:
'max_request' => 10000
Description: The maximum number of TCP connections allowed to be maintained by the server
Description: When this parameter is set, new connections are rejected when the number of connections already on the server reaches this value.
In addition, the value of this parameter must not exceed the value of operating
system ulimit -n,
and this value should not be set too large, because swoole_server will request a large chunk of memory at once to hold the information for each connection.
Example:
'max_conn' => 10000
Description: Set how processes communicate with each other.
Description: There are three modes of communication, the parameters are as follows:
- 1
- 2
- 3 . . . .
Example:
'ipc_mode' => 1
Description: Specify a packet distribution policy.
Description: There are three modes with the following parameters:
- 1 . . . . round robin mode, receiving a round robin assigned to each worker process
- 2 fixed mode, assigning the worker according to the connected file descriptor. This ensures that data from the same connection is processed only by the same worker
- In preeptive mode, the main process selects the delivery based on the worker's free and busy state and only delivers it to the idle worker
Example:
'dispatch_mode' => 2
Description: The number of task processes turned on by the server.
Description: When this parameter is set, the server turns on the asynchronous task function.
You can now use the
task
method to post asynchronous tasks.
After you set this parameter, you must swoole_server onTask/onFinish callback functions for the user, or the startup server will report an error.
Example:
'task_worker_num' => 8
Description: The maximum number of tasks allowed to be processed per task.
Description: Refer
to max_request
task_worker_num
Example:
'task_max_request' => 10000
Description: Set how the task process communicates with the worker process.
Description: Refer
to ipc_mode
Example:
'task_ipc_mode' => 2
Description: The setup program enters the background and runs as a daemon.
Description: This must be enabled for long-running server-side programs. I
f the daemon is not enabled, the program will be terminated when the ssh terminal exits.
When daemon is enabled, standard inputs and outputs are
redirected to log_file,
and if log_file is
not set, all outputs are discarded.
Example:
'daemonize' => 0
Description: Specify the log file path
Description: Exception information that occurs during the swoole run is recorded in this file. T
he default is printed to the screen.
Note log_file does
not automatically slice a file, so you
need to clean it up regularly.
Example:
'log_file' => '/data/log/swoole.log'
Description: Set the heartbeat detection interval
Description: This option represents how often round, in seconds.
Traversing all connections with each detection, forcing a connection to close if no data is sent during the interval (there will be an onClose callback).
Example:
'heartbeat_check_interval' => 60
Description: Set the maximum idle time allowed for a connection.
Description: This parameter is
used in conjunction heartbeat_check_interval the
data. E
ach time you traverse all connections, force the
connection to close if heartbeat_idle_time no
data is sent within the heartbeat_idle_time time.
The default
setting heartbeat_check_interval
is 2.
Example:
'heartbeat_idle_time' => 600
Description: Turn on the eof detection function
Description: Use
package_eof
with the . T
his option detects data from client connections and delivers
packets to
the Worker process when the packet ends with the specified package_eof string, otherwise the packets are stitched until the cache overflows or timeouts.
In the event of an error, the connection is determined to be malicious, and packets are dropped and forced to close the connection.
EOF detection does not look for eof strings from the middle of the data, so the Worker process may receive multiple packets at the same time and need to split the packets itself $data in the application layer code
Example:
'open_eof_check' => true
Description: Set the EOF string
Description: package_eof allows only
8 bytes of strings to be passed
in
Example:
'package_eof ' => '/r/n'
Description: Open package length detection
Description: The packet length detection
provides the resolution of the fixed package
head and package body this format protocol.
When enabled, you can guarantee that the Worker process, onReceive, will receive a complete packet each time.
Example:
'open_length_check' => true
Description: The first few bytes in the header begin to hold the length field
Description: Use
with open_length_check to
indicate the location of the length field.
Example:
'package_length_offset' => 5
Description: The length is calculated from the first few bytes.
Description: Use
with open_length_check to
indicate the length of the head.
Example:
'package_body_offset' => 10
Description: Specifies the type of package length field
Description: Use
with open_length_check,
specify the type of length field, and the parameters are as follows:
- 's' is used to int16_t order of machine bytes
- 'S' is used uint16_t machine byte order
- The 'n' is uint16_t the large-end byte sequence
- The 'N' is uint32_t large-end byte order
- 'L' is used uint32_t machine byte order
- 'l' is the order of the machine bytes
Example:
'package_length_type' => 'N'
Description: Set the maximum packet size
Description: This value determines the size of the packet cache. I
f the cached data exceeds this value, an error is thrown.
Specific error handling is determined by the type of protocol resolution that is turned on.
Example:
'package_max_length' => 8192
Description: Enable CPU affinity settings
Description: In a multi-core hardware platform, enabling this feature binds the swoole's actor thread/worker process to a fixed core.
You can avoid the runtime of a process/thread switching between multiple cores and increase the hit rate of CPU Cache.
Example:
'open_cpu_affinity' => true
Description: Enable open_tcp_nodelay
Description: When the TCP connection is turned on, the Nagle merge algorithm is not turned off and immediately sent to the client connection.
In some scenarios, such as http servers, you can improve responsiveness.
Example:
'open_tcp_nodelay' => true
Description: Enable tcp_defer_accept features
Description: After startup, accept is triggered only when a TCP connection has data to send.
Example:
'tcp_defer_accept' => true
Description: Set up SSL tunnel encryption
Description: Set the value to a string of file names, specifying the
path to the cert
certificate
and key.
Example:
'ssl_cert_file' => '/config/ssl.crt',
'ssl_key_file' => '/config//ssl.key',
Description: Turn on the options for KEEP_ALIVE TCP
Description: Use TCP's built-in keep_alive properties to ensure that connections are not closed because they are idle for long hours.
Example:
'open_tcp_keepalive' => true
Description: Specify the probe interval.
Description:
With open_tcp_keepalive,
probe if a
connection does tcp_keepidle
data within the data source.
Example:
'tcp_keepidle' => 600
Description: Specifies the packet interval at the time of the probe
Description: Use
with open_tcp_keepalive
system
Example:
'tcp_keepinterval' => 60
Description: Specifies the number of attempts to probe
Description: With
open_tcp_keepalive,
if
tcp_keepcount is
still unsys response after two attempts, the connection is determined to be closed.
Example:
'tcp_keepcount' => 5
Description: Specifies the length of the Listen queue
Description: This parameter will determine how many connections are waiting for acept at the same time.
Example:
'backlog' => 128
Description: Specifies the number of Actor threads
Description: Set the number of event processing threads in the main process, the default will enable the same number of CPU cores, generally
set to 1-4
times the CPU core, the maximum number of CPU cores.
Example:
'reactor_num' => 8
Description: Set up a temporary directory of data for task
Description: In swoole_server, if more than 8192 bytes of data is posted, temporary files are enabled to hold the data.
The task_tmpdir here is to set the location where temporary files are saved.
Swoole-1.7.7 plus is required
Example:
'task_tmpdir' => '/tmp/task/'
In addition to the 29 options above, there are a few that are not commonly used or that have been discarded. In the future, if there is actual demand, it will be added.