[ruby-core:105116] [Ruby master Bug#18144] Timeout not working while regular expression match is running

Issue #18144 has been reported by duerst (Martin D=FCrst).

----------------------------------------
Bug #18144: Timeout not working while regular expression match is running
https://bugs.ruby-lang.org/issues/18144

* Author: duerst (Martin D=FCrst)
* Status: Third Party's Issue
* Priority: Normal
* ruby -v: various, see description
* Backport: 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN
----------------------------------------
Experimenting with dozens of regular expressions that take a long time to m=
atch against certain strings, I have found that for some regular expression=
 matches, Timeouts don't work at all (while they work for the rest without =
problems).

The attached file allows reproduction. On three different machines and with=
 six different versions of Ruby (see below), the attached file always showe=
d about 20~25 seconds of execution time even though there was a Timeout int=
erval of only 10s. If your machine is too fast so that the printed-out resu=
lt comes in below or just a bit above 10s, then either lower the timeout du=
ration (e.g. to 5s) or increase the length of the string (e.g. 80_000 -> 10=
0_000; caution, time increases with the second power of this number).

The timeout uses `Timeout::timeout` and `rescue Timeout::Error` as describe=
d in the pickaxe.

Checked with the following versions/environments:
- ruby 3.1.0dev (2021-06-03T06:59:33Z master 7e14762159) [x86_64-linux] on =
Ubuntu on WSL on a Windows 10 notebook
- ruby 2.6.4p104 (2019-08-28 revision 67798) [x86_64-cygwin] on same notebo=
ok
- ruby 3.0.0p0 (2020-12-25 revision 95aff21468) [x64-mingw32] on same noteb=
ook
- ruby 3.1.0dev (2021-06-03T06:59:33Z master 7e14762159) [x86_64-linux] on =
Ubuntu on WSL on same notebook
- ruby 2.7.0p0 (2019-12-25 revision 647ee6f091) [x86_64-linux-gnu] on a two=
-CPU Dell server with Ubuntu
- ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux] on an older Dell=
 server with CentOS


---Files--------------------------------
no_timeout.rb (333 Bytes)


-- =

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

Unsubscribe: <mailto:[e-mail]?subject=3Dunsubscribe>
<http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>