Redis pipeline technology

Redis pipeline technology

Redis is a TCP service based on a client-service-side model and a request/response protocol. This means that typically a request follows the following steps:

• The client sends a query request to the service side and listens for Socket to return, usually in blocking mode, waiting for the service side to respond.
• The service side processes the command and returns the results to the client.

Redis pipeline technology

Redis pipeline technology allows clients to continue sending requests to the service side and eventually read all service-side responses at once when the service side is not responding.

Instance

To view the redis pipeline, you only need to launch the redis instance and enter the following command:

$(echo -en "PING\r\n SET w3ckey redis\r\nGET w3ckey\r\nINCR visitor\r\nINCR visitor\r\nINCR visitor\r\n"; sleep 10) | nc localhost 6379

+PONG
+OK
redis
:1
:2
:3

In the above example we use the PING command to see if the redis service is available, and then we set the value of w3ckey to redis, and then we get the value of w3ckey and increase the visitor three times.

In the results returned, we can see that these commands are committed to the redis service at once and eventually read all service-side responses at once

Advantages of pipeline technology

The most significant advantage of pipeline technology is the improved performance of the redis service.

Some test data

In the following tests, we will use Redis' Ruby client to support pipeline technology features and test the speed improvement of pipeline technology.

require 'rubygems' 
require 'redis'
def bench(descr) 
start = Time.now 
yield 
puts "#{descr} #{Time.now-start} seconds" 
end
def without_pipelining 
r = Redis.new 
10000.times { 
  r.ping 
} 
end
def with_pipelining 
r = Redis.new 
r.pipelined { 
    10000.times { 
        r.ping 
   } 
} 
end
bench("without pipelining") { 
 without_pipelining 
} 
bench("with pipelining") { 
    with_pipelining 
}

Data from this simple script above from a Mac OS X system on a local area network shows that the round-trip delay has improved considerably since the pipeline operation was opened.

without pipelining 1.185238 seconds 
with pipelining 0.250783 seconds

As you can see, when we open the pipe, we're five times faster.