[lfs-dev] perl tests loop at 100% CPU in current SVN

Ken Moffat zarniwhoop at ntlworld.com
Mon Aug 8 13:26:55 PDT 2016

On Mon, Aug 08, 2016 at 02:04:10AM +0100, Ken Moffat wrote:
> That box used to be my development machine, so it has several
> filesystems for building.  And I urgently need a fresh system to
> look at texlive re the tlmgr ticket.  So, since my 20160527 build
> worked on the haswell, I'll use a fresh partition and try that
> version for LFS.
A (minimal) progress update -

1. perl tests are *supposed* to take 100% CPU if they don't do I/O.
But they are not supposed to run for ever.

2. The 20160527 build seemed to be stuck at the same place (running
a 4.7.0 kernel).

3. I rebooted to a 4.6.0 kernel and retried, but after about 30 min
I built gdb, saw it seemed to be in libpthread (a lack of debugging
info), killed it.

4. On the host (svn from June last year), still using 4.6.0, I
tried building and testing perl-5.24.0 : the tests completed in
45m03, but with the following failures -

Failed 3 tests out of 2245, 99.87% okay.

 and for the first two -

t/itimer.t: overall time allowed for tests (360s) exceeded!
FAILED--expected 2 tests, saw 1

lib/Benchmark .................................................
Illegal division by zero at ../lib/Benchmark.t line 77.
# Looks like you planned 213 tests but ran 10.
# Looks like your test exited with 255 just after 10.
FAILED--expected 213 tests, saw 10

5. At that point I went back to the haswell, which is runnning the
20160527 build with a 4.7.0 kernel, to try building and testing
perl: all fine, less than 8 minutes for the tests.

6. Came back to the AMD, running 4.6.0, retried perl in chroot -
the tests have been running for 80 minutes so far, still in
lib/Benchmark - I'll let it run for a bit longer.

At the moment I suspect some of it might be down to an inopportune
kernel config, but I suppose I got lucky in the manual run (test
terminated after division by zero).  I'll give that another go, then
think about changing my kernel config to be closer to the haswell.

`I shall take my mountains', said Lu-Tze. `The climate will be good
for them.'     -- Small Gods

More information about the lfs-dev mailing list