[RFA/testsuite] Reduce the default test timeout to 30 seconds for Unix.

[RFA/testsuite] Reduce the default test timeout to 30 seconds for Unix.

[Joel Brobecker]

Hello,

This is something that I noticed while working on testcase timeouts...

This patch reduces the timeout duration used for all "unix" native
configurations from 60 seconds down to 30 seconds.  Even under NFS
and heavy loads, 60 seconds seems a bit excessive.

This might not be very important if we manage to find a way to implement
the idea of aborting a testcase as soon as the first timeout gets hit.
But in the menatime, this reduces significantly the amount of time spend
multi-timing out... (no idea on how to do that so far, though)

In the few situations where 30 seconds, which is already 3 times the
dejagnu default, is not enough, the user has the possibility of changing
the timeout duration back to any value by definining gdb_test_timeout.

gdb/testsuite/ChangeLog:

        * config/unix.exp (timeout): Change value to 30.

Tested on x86_64-linux.  No regression.

Any objection?
Thanks,
-- 
Joel

---
 gdb/testsuite/config/unix.exp |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/gdb/testsuite/config/unix.exp b/gdb/testsuite/config/unix.exp
index 711b461..c4ca444 100644
--- a/gdb/testsuite/config/unix.exp
+++ b/gdb/testsuite/config/unix.exp
@@ -20,7 +20,7 @@
 # accepting whatever default dejagnu gives us (apparently 10 seconds).
 # When running the tests over NFS, under somewhat heavy load, 10 seconds
 # does not seem to be enough.  Try starting with 60.
-set timeout 60
+set timeout 30
 verbose "Timeout is now $timeout seconds" 2
 
 load_lib gdb.exp
-- 
1.6.3.3

Re: [RFA/testsuite] Reduce the default test timeout to 30 seconds for Unix.

[Mark Kettenis]

> From: Joel Brobecker <brobecker@adacore.com>
> Date: Mon,  8 Feb 2010 16:25:09 +0400
> 
> Hello,
> 
> gdb/testsuite/ChangeLog:
> 
>         * config/unix.exp (timeout): Change value to 30.
> 
> Tested on x86_64-linux.  No regression.

I think that for this to be meaningful, you should really test this on
a slower platform though.  Something like a native linux config on arm
should do the trick.

Re: [RFA/testsuite] Reduce the default test timeout to 30 seconds for Unix.

[Joel Brobecker]

> > gdb/testsuite/ChangeLog:
> > 
> >         * config/unix.exp (timeout): Change value to 30.
> > 
> > Tested on x86_64-linux.  No regression.
> 
> I think that for this to be meaningful, you should really test this on
> a slower platform though.  Something like a native linux config on arm
> should do the trick.

I agree.  The problem is that I had to test on at least one platform,
and I don't have access to that many machines that are very noticeably
slow, particularly the system that you suggest.  I could tell you about
one of our old x86-solaris machines, but I am under surveillance and
will get killed if I even attempt the gdb-testsuite there.

I think the slowest I have is ppc-aix, but even that I think is way too
fast to trigger the timeout (I consider that, for the programs in our
testsuite, anything other than an "immediate" response is a bug).

All in all, I think the fairest test would be to try with a configuration
where communication with the target is really slow, something over the
serial line.  But we don't have any such configuration at AdaCore.

That being said, it's a shame to potentially penalize almost everyone
just because some systems might be too slow for the default 10 seconds
timeout. I thought that 30 secs was a good compromise for today's
equipment (meaning today's outdated equipment).  If there are still
some such systems out there where 30secs is not enough, they can very
easily change the timeout duration back.

It's fine if we decide to be conservative and not apply this patch
without more testing.  But I think we should just give it a try, and see
what happens.  We have very little to lose. It's really easy to further
adjust the timeout if some of the developers notice that 30 secs is
too small, or even revert.  But I suspect/hope that this will only ever
happen with specific non-unix configuration, where they already use a
board file that they'll instantly update to get a longer timeout.

-- 
Joel