# There's a deadlock in code in the PickAxe, and I'm not seein **URL:** \ **Category:** Ruby\ **Created:** [January 17, 2006, 1:24am UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601 "2006-01-17T01:24:41Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![dirtytree](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@dirtytree](https://www.ruby-forum.com/u/dirtytree)\ **Post date:** [January 17, 2006, 1:24am UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601/1 "2006-01-17T01:24:41Z")
The following code (form pg. 739) deadlocks with a large count. What am I missing? Cheers Dave require ‘thwait’ require ‘sync’ class Counter attr\_reader :total\_count def initialize @total\_count = 0 @count\_down = 0 @sync = Sync.new end def inc @sync.synchronize(:EX) do @total\_count += 1 @count\_down -= 1 end end def test\_consistent @sync.synchronize(:SH) do fail “Bad counts” unless @total\_count + @count\_down == 0 end end end count = Counter.new waiter = ThreadsWait.new([]) # create 10 threads that each inc() 10,000 times 10.times do waiter.join\_nowait(Thread.new { 100\_000.times do count.inc count.test\_consistent end }) end p waiter.all\_waits p count.total\_count ---
**Author:** ![dirtytree](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@dirtytree](https://www.ruby-forum.com/u/dirtytree)\ **Post date:** [January 17, 2006, 1:58am UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601/2 "2006-01-17T01:58:05Z")
Dave T. wrote: > The following code (form pg. 739) deadlocks with a large count. What am > I missing? Ok here, with ruby-1.8.4, Linux 2.6.12, Ubuntu. I tried 100 threads, 10\_000 iterations, too. ---
**Author:** ![dirtytree](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@dirtytree](https://www.ruby-forum.com/u/dirtytree)\ **Post date:** [January 21, 2006, 3:40pm UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601/3 "2006-01-21T15:40:27Z")
On Tue, 17 Jan 2006, Dave T. wrote: > The following code (form pg. 739) deadlocks with a large count. What am I > missing? works for me on mac and linux. what are you on? -a ---
**Author:** ![dirtytree](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@dirtytree](https://www.ruby-forum.com/u/dirtytree)\ **Post date:** [January 21, 2006, 3:40pm UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601/4 "2006-01-21T15:40:37Z")
On 1/16/06, Dan H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Hummmm, no help here, works fine for me. > > Ruby 1.8.2, RH-8… Same for Ruby 1.8.3 on Ubuntu i486-linux. ---
**Author:** ![dirtytree](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@dirtytree](https://www.ruby-forum.com/u/dirtytree)\ **Post date:** [January 21, 2006, 3:40pm UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601/5 "2006-01-21T15:40:38Z")
On Jan 16, 2006, at 4:41 PM, removed\_email\_address@domain.invalid wrote: > > The following code (form pg. 739) deadlocks with a large count. > > What am I missing? > > works for me on mac and linux. what are you on? OSX/ruby 1.8.2 (2004-12-30) [powerpc-darwin8.2.0] dave[CVS/rubybook 19:52:46] ruby t.rb deadlock 0x3a4e40: sleep:J(0x3b090c) - /Users/dave/ruby1.8/lib/ruby/ 1.8/thwait.rb:121 deadlock 0x3b090c: sleep:- - /Users/dave/ruby1.8/lib/ruby/1.8/ sync.rb:150 … deadlock 0x1b4af4: sleep:- - /Users/dave/ruby1.8/lib/ruby/1.8/ sync.rb:150 deadlock 0x1d5790: sleep:- (main) - /Users/dave/ruby1.8/lib/ruby/1.8/ thread.rb:281 /Users/dave/ruby1.8/lib/ruby/1.8/thwait.rb:119:in `pop': Thread (0x3ca744): deadlock (fatal) from /Users/dave/ruby1.8/lib/ruby/1.8/thwait.rb:139:in`next\_wait’ from /Users/dave/ruby1.8/lib/ruby/1.8/thwait.rb:154:in `all\_waits’ from t.rb:35 It doesn’t always do it, but with 100,000 iterations, it does it most of the time. Interestingly, it doesn’t seem to do it with the precompiled Ruby. I’m wondering if I build my local version with the wrong threading options: the Apple build has --enable-pthread, and mine doesn’t Anyone know if that would cause a problem? Dave ---
**Author:** ![dirtytree](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@dirtytree](https://www.ruby-forum.com/u/dirtytree)\ **Post date:** [January 21, 2006, 3:40pm UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601/6 "2006-01-21T15:40:30Z")
Hummmm, no help here, works fine for me. Ruby 1.8.2, RH-8… pridith:[2006.01.16-15:54]:time ./threads.rb nil 1000000 32.200u 0.013x 0:32.59 99.1% 0+0k 0+0io 231pf+0w pridith:[2006.01.16-15:56]: -dwh- On Mon, 2006-01-16 at 15:33, Dave T. wrote: > def inc > end > end > > p waiter.all\_waits > p count.total\_count – I not only live each endless day in grief, but live each day thinking about living each day in grief. – C.S. Lewis Daniel W. Hinz Xerox Corp: XOG/SEBU/MCD/EIDC/ISM&D MS: 111-03J e-mail: removed\_email\_address@domain.invalid 800 Phillips Road TEL: 585.422.8078 Webster, NY 14580 ---
**Author:** ![dirtytree](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@dirtytree](https://www.ruby-forum.com/u/dirtytree)\ **Post date:** [January 21, 2006, 3:40pm UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601/7 "2006-01-21T15:40:39Z")
On 2006.01.17 11:09, Dave T. wrote: > Indeed, rebuilding my local Ruby with --enable-pthread fixes it. Is > this a bug in threading? It seems to work OK here both ways. OSX threading, perhaps? ruerue@yawn$ ruby -v ruby 1.8.4 (2005-12-24) [amd64-freebsd6] > Dave E ---
**Author:** ![dirtytree](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@dirtytree](https://www.ruby-forum.com/u/dirtytree)\ **Post date:** [January 21, 2006, 3:40pm UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601/8 "2006-01-21T15:40:38Z")
On Jan 16, 2006, at 8:02 PM, Dave T. wrote: > Interestingly, it doesn’t seem to do it with the precompiled Ruby. > I’m wondering if I build my local version with the wrong threading > options: the Apple build has --enable-pthread, and mine doesn’t > > Anyone know if that would cause a problem? Indeed, rebuilding my local Ruby with --enable-pthread fixes it. Is this a bug in threading? Dave ---
**Author:** ![dirtytree](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/aeb1de/32.png) [@dirtytree](https://www.ruby-forum.com/u/dirtytree)\ **Post date:** [January 21, 2006, 3:44pm UTC](https://www.ruby-forum.com/t/theres-a-deadlock-in-code-in-the-pickaxe-and-im-not-seein/52601/9 "2006-01-21T15:44:28Z")
> On Tue, 17 Jan 2006, Dave T. wrote: > > The following code (form pg. 739) deadlocks with a large count. What > am I > missing? Works on Ruby 1.8.2, WinXP. jf