# \[1.9\] Queue$B$N(Bfairness

**URL:** <https://www.ruby-forum.com/t/1-9-queue-b-n-bfairness/192334>\
**Category:** Development\
**Created:** [July 28, 2010, 1:04pm UTC](https://www.ruby-forum.com/t/1-9-queue-b-n-bfairness/192334 "2010-07-28T13:04:33Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![NAKAMURAS\_Hiroshi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/f1d935/32.png) [@NAKAMURAS\_Hiroshi](https://www.ruby-forum.com/u/NAKAMURAS_Hiroshi)\
**Post date:** [July 28, 2010, 1:04pm UTC](https://www.ruby-forum.com/t/1-9-queue-b-n-bfairness/192334/1 "2010-07-28T13:04:33Z")

</div>

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# [fair-but-slow-queue-for-1.9.diff · GitHub](http://gist.github.com/493930#file_gistfile1.rb)

create\_waiter = lambda { |name, command|  
t = Thread.new {  
p [command.pop, name]  
}  
Thread.pass until t.status == ‘sleep’  
t  
}

50.times do  
command = Queue.new

# create 3 waiters, and…

create\_waiter.call(:first, command)  
create\_waiter.call(:second, command)  
create\_waiter.call(:third, command)

# and pushes a command.

command.push(:go)

# then try to consume the command by a subsequent thread

Thread.new {  
p [command.pop, :LATER]  
}  
end

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:LATER]e$B$J$Ie(B  
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# [gist:430066 · GitHub](http://gist.github.com/430066)

require ‘thread’

q = Queue.new  
t1 = Thread.new {  
p [:t1, q.pop]  
q.push(:t1)  
}

q.push(:main)  
p [:main, q.pop]

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