RFR: 8260555: Change the default TIMEOUT_FACTOR from 4 to 1 [v3]

[David Holmes]

On Tue, 19 Aug 2025 05:23:15 GMT, David Holmes <dholmes at openjdk.org> wrote:

>> Take test test/hotspot/jtreg/compiler/arraycopy/stress/TestStressArrayCopy.java as example.
>> If there is a bug in jvm with -Xcomp option which will cause this test run time outed. Before this PR, it will take `7200*10` seconds to run this test finish and report time outed failure. But after this PR, it will take `28800*10` seconds to run this test finish ang then report timed out failure. I think the `28800*10` senonds is too long and it's unacceptable.
>
> DELETED - I confused the timeout with the timeout-factor. New comment below.

No change should be made to any explicit setting of the timeoutFactor in general as that could cause mass timeouts to occur (old default timeout = 120 * 10 = 1200 but new default = 120 * 2.5 = 300!). 

However I see the concern of @sendaoYan because individual tests may now get much larger timeout values when run with the non-default timeoutFactor because they have been adjusted for the new default. I don't see any solution to this dilemma.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/26749#discussion_r2284161138