Asynchronous PHP
Myth? Reality!
Alexander Lisachenko,
Head of Sowtware Architecture at Alpari (RU)
About me
About me
Alexander Lisachenko
• Software Architect at Alpari
• Passionate developer
• Author of Go! Aspect-Oriented framework for
PHP
• Symfony2 prophet (SOA, DI, IoC, Varnish)
Coordinating over 30 instances of Symfony2 in
Alpari, including www.alpari.ru
Twitter: @lisachenko
Github: https://github.com/lisachenko
Technology Evolution
Technology Evolution
Personal Home Pages 
Simple blogs
E-Commerce markets
Social applications
Highload
What should we expect
in the nearest future?
Technology trends
More Complex systems
More data (Big Data)
More Faster processing
More Scalable systems
More Real-Time (OLTP)
PHP World
Simple example
What if
sharding?
What if
unavailable?
Highload?
Blocking IO
IO
(TCP)
buyAction
IO
(DB)
Withdrawal
Process
IO
(Mail)
What is the solution?
Asynchronous PHP
• Soap one-way calls
• DB: reap_async_query,
• CLI processes: exec,
mysqli_poll,
popen, proc_open
pg_send_query
• CLI signals:
• Selecting:
pcnt_signal_dispatch,
curl_multi_select,
ticks,
socket_select,
register_tick_function
stream_select,
• Message Queues
stream_set_blocking
• Threads (pthreads
extension)
One-way SOAP call
One-way SOAP call
No output is defined for the
operation
One-way SOAP call
Works only in WSDL-mode, so need an WSDL
(Zend_AutoDiscover):
Only “input” part is defined for
one-way call
One-way SOAP call – client side
Positive
• Immediately returns
• Service architecture
• Asynchronous
Negative
• Can not handle errors
• Unreliable
CLI tools
Processes
Processes. Elementary
Positive
• Asynchronous
• Can be used inside
web requests
Negative
• No return values
• No callbacks
• Detect completion?
Processes. Intermediate
Non-blocking stream, we can
query it later asynchronously
with stream_select()
Processes. Intermediate
Positive
stream_select()
Asynchronous goodness
•
• Full control over IO
• Non-blocking mode
Negative
• A bit complex  POSIX signals
• No callbacks
• Sync loops
Processes. POSIX signals
Processes. POSIX signals
Process 1
• posix_kill($pid2, SIGHUP)
UNIX Kernel
Process 2
• pcnt_signal()
• pcnt_signal_dispatch()
Signal handling issue in the code
PHP will hang until loop is
finished and will ignore signals
Asynchronous signal handling
Enable support for tick handler
and async signal handling.
Asynchronous PHP. Enterprise way.
Asynchronous PHP. Enterprise way.
Publishers
Subscribers
PHP App1
PHP App2
PHP App4
M
e
s
s
a
g
e
Q
u
e
u
e
PHP App3
PHP App5
PHP App6
STOMP,
WebSocket,
AMQP
Asynchronous PHP. Enterprise way.
Asynchronous PHP. Enterprise way.
Positive
•
•
•
•
Negative
• Require SOA
• Complex solution
Scalability
Automatic failover
Cross-platform
Low coupling
Asynchronous data access in PHP
Asynchronous data access in PHP
Like typical
stream_select() call
Asynchronous PHP. Cutting-edge.
Asynchronous PHP. Cutting-edge.
True threads in PHP!
Just call a function in
the separate thread
Thread
syncrhronization
Asynchronous PHP. Cutting-edge.
yields a threadcoroutine
Asynchronous PHP. Cutting-edge.
Threaded asynchronous socket server
Non-blocking server
Our threaded server
Effective epoll() loop in
libevent
Threaded asynchronous socket server
Non-blocking
connection
Threaded asynchronous socket server
Each connection is
handled in separate thread
Separate loop for each
connection
Thanks! Questions?
Alexander Lisachenko
Twitter: https://twitter.com/lisachenko
Github: https://github.com/lisachenko