From: "mperham (Mike Perham)" <mperham@...>
Date: 2013-04-27T02:04:42+09:00
Subject: [ruby-core:54605] [ruby-trunk - Bug #8335] Performance regression with many threads


Issue #8335 has been updated by mperham (Mike Perham).


I have some concern about #8211 so here's the info.  Each VM was installed via rbenv.

> ruby -v
ruby 1.9.3p374 (2013-01-15 revision 38858) [x86_64-darwin12.3.0]
> ruby -e 'puts RUBY_DESCRIPTION, RbConfig::CONFIG["cflags"], RbConfig::CONFIG["CFLAGS"]'
ruby 1.9.3p374 (2013-01-15 revision 38858) [x86_64-darwin12.3.0]
 -O3 -ggdb -Wall -Wextra -Wno-unused-parameter -Wno-parentheses -Wno-long-long -Wno-missing-field-initializers -Werror=pointer-arith -Werror=write-strings -Werror=declaration-after-statement -Werror=shorten-64-to-32 -Werror=implicit-function-declaration
-g -O2  -Wno-error=shorten-64-to-32 -pipe

> rbenv shell 2.0.0-p0
> ruby -v
ruby 2.0.0p0 (2013-02-24 revision 39474) [x86_64-darwin12.3.0]
> ruby -e 'puts RUBY_DESCRIPTION, RbConfig::CONFIG["cflags"], RbConfig::CONFIG["CFLAGS"]'
ruby 2.0.0p0 (2013-02-24 revision 39474) [x86_64-darwin12.3.0]
 -O3 -fno-fast-math -ggdb3 -Wall -Wextra -Wno-unused-parameter -Wno-parentheses -Wno-long-long -Wno-missing-field-initializers -Wunused-variable -Werror=pointer-arith -Werror=write-strings -Werror=declaration-after-statement -Werror=shorten-64-to-32 -Werror=implicit-function-declaration
  -Wno-error=shorten-64-to-32 -pipe

----------------------------------------
Bug #8335: Performance regression with many threads
https://bugs.ruby-lang.org/issues/8335#change-38933

Author: mperham (Mike Perham)
Status: Open
Priority: Normal
Assignee: 
Category: 
Target version: 
ruby -v: ruby 2.0.0p0 (2013-02-24 revision 39474) [x86_64-darwin12.3.0]
Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN


I've created a simple case to reproduce a performance problem with Sidekiq.  A customer is using 200 worker threads to process background jobs and finding it to be quite slow.  To process 50,000 jobs, it takes Ruby 1.9.3 about 200 seconds.  With Ruby 2.0, the time required is almost double.  Please see instructions to reproduce the problem here:

https://github.com/mperham/sidekiq/tree/master/myapp#ruby-20-slowness-with-big-concurrency


-- 
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