[ruby-core:65993] [ruby-trunk - Bug #10009] IO operation is 10x slower in multi-thread environment

Issue #10009 has been updated by Alexandre Riveira.

File test.py added


Following script in python to buy blocking io python x ruby

Results:

ruby without changes TIME_QUANTUM_USEC (100 * 1000)
first..........: 32445253
second.........: 30660119
postgres.......: 61
time...........: 1.5022704 secs


ruby with TIME_QUANTUM_USEC (1 * 1000)

first..........: 17793384
second.........: 17438453
postgres.......: 4638


python

first 17498064
postgres 2027
third 18702539



----------------------------------------
Bug #10009: IO operation is 10x slower in multi-thread environment
https://bugs.ruby-lang.org/issues/10009#change-49726

* Author: Alexandre Riveira
* Status: Open
* Priority: Urgent
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.1 x ruby 1.9.2 with taskset
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
I created this issue #9832 but not have io operation.
In the script attached I simulate IO operation in multi-thread environment.
For ruby 1.9.2 apply `taskset -c -p 2 #{Process.pid}` for regulates threads behavior.
The second Thread is a io operation

My results:

1) ruby 2.1.2
first 43500194
second 95
third 42184385

2) ruby-2.0.0-p451
first 38418401
second 95
third 37444470

3) 1.9.3-p545
first 121260313
second 50
third 44275164

4) 1.9.2-p320
first 31189901
second 897 <============
third 31190598

Regards


Alexandre Riveira


---Files--------------------------------
teste_thread_schedule_2.rb (1.05 KB)
teste_thread_schedule.py (953 Bytes)
teste_thread_schedule.rb (955 Bytes)
test_thread_sched_pipe.rb (1.01 KB)
test_thread_sched.rb (2.82 KB)
test_thread_sched.rb (2.88 KB)
tests.txt (2.5 KB)
test.py (1.41 KB)


-- 
https://bugs.ruby-lang.org/