Hi Paul,
These measurements:
> * in virtual machines with 8 CPUs:
>
> - Ubuntu 22.04 60 sec (4 CPUs: 15 sec)
>
> * outside VirtualBox:
>
> - Ubuntu 22.04 (12 CPUs) 6 sec
together with the investigation of the pthread_cond_timedwait "bug",
makes it sound possible that a hypervisor is exercising some influence.
I would therefore be interested in the result of the following
experiment:
1. Install a toolchain for creating binaries linked against musl-libc:
$ sudo apt install musl-gcc
2. Create a testdir for the module 'pthread-rwlock'.
3. Build it with CC="gcc". You should still see the test failure after
10 minutes.
4. Build it with CC="musl-gcc". Run
$ time gltests/test-pthread-rwlock
If 4. takes more than 30 seconds, your OS is probably running on top of
a hypervisor, and that is causing the problem.
If 4. takes just a few seconds, it looks like a glibc bug.
Bruno
