You should be worried about more than Time::HiRes. Although the module shouldn't fail, you have potentially bigger problems:

• You seem to be using Debian 6 "Squeeze". Long-term support for that ended in 2014 (ten years ago) if Wikipedia is to be trusted. That potentially means you are missing a decade of security bugfixes.
• You are using a 32bit operating system. These have all kinds of limitations. Including that your OS (or major libraries installed in it) potentially still use 32bit timestamps. Or use a mix of 32/64 bit timestamps, which certainly could explain some of the problems if your filesystem timestamp bitsize mismatches Perl.
• It seems even the Debian maintainers are thinking of sunsetting 32bit distros.

As for me, i can't even test Time::HiRes on a 32 bit system anymore, because i have upgraded the last one more than a decade ago. I might have some ancient Raspberry PI around in some spare parts box that i could potentially get running again. But this bug might be processor/file system specific. What filesystem are you running on?

Hi cavac, thanks for the reply. You raised good questions. I'd like to get a couple more years use out of this laptop but I see that I could run into problems.

You wrote:
  >You are using a 32bit operating system. These have all kinds of limitations. Including that your OS (or major libraries installed in it) potentially still use 32bit timestamps. Or use a mix of 32/64 bit timestamps, which certainly could explain some of the problems if your filesystem timestamp bitsize mismatches Perl.

It's a bit strange because I similarly "renovated" an older laptop a few months ago with a fresh OS install (the last Debian available for 32-bit machines, 4.19) and didn't see any test failures like these when I built perl and modules, that machine runs a 32-bit AMD processor and the machine in question here runs an Intel i5.

  >What filesystem are you running on?

I'm using the ext4 filesystem.

Although probably based on Squeeze as you say, this machine actually got Linux Mint (LMDE) installed on it. Mint seems to be supporting 32-bit boxes long than Debian themselves.

Thanks again for your time and attention and suggestions.

Mar 05, 2025 at 19:46 UTC

Is this laptop running a 32bit-only processor? How old is it?

I have a 14 to 15 year old laptop around that i still occasionally use. I run Xubuntu 22.04 LTS (64 bit) on it and it performs reasonably well. For me, the thing that makes modern Linux on older hardware work is selecting a Desktop environment that uses few resources but still has all the modern convenience. In my case, that's XFCE. It's highly configurable, and it got a decent terminal emulator (and if you need a high performance terminal, xterm is a good choice, at least for me terminal graphics demos).

I'd recommend trying to run a few 64 bit Linux distris as live system from an USB stick to see if they boot. (X)Ubuntu also has a settings program usually called "Additional drivers" that, so far, hasn't let me down when it comes to supporting graphics cards.

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Perl (including Time::HiRES) is regularly tested against a 32-bit Linux userland, and Debian still provide 32-bit installation images.

That Debian version number looks strange, I only ever recall seeing major.minor versions for Debian. If it is Debian you should have a /etc/debian_version file with the release number.

You can run just the failing test with:

which may provide some clues as to what's going on.

You say you're using the latest Debian archive, do you see the same failure if you build from the origin perl 5.40.1 sources?

Hey tonyc. Thanks, you taught me something. I ran ./perl harness -v ../dist/Time-HiRes/t/utime.t and the output (trimmed out a little bit of non-relevant stuff for readability):

../dist/Time-HiRes/t/utime.t .. 

# Testing for subsecond file timestamps (mtime) in /home/somian/build/perl/perl-debian-5.40/dist/Time-HiRes
# Subsecond file timestamps in /home/somian/build/perl/perl-debian-5.40/dist/Time-HiRes: OK
1..22
# $^O = linux, atime = 1.111111111, mtime = 2.222222222
# utime $fh
ok 1 - One file changed
not ok 2 - atime set correctly

#   Failed test 'atime set correctly'
#   at t/utime.t line 156.
#          got: '1'
#     expected: '1.111111111'
not ok 3 - mtime set correctly

#   Failed test 'mtime set correctly'
#   at t/utime.t line 158.
#          got: '2'
#     expected: '2.222222222'
#utime $filename
ok 4 - One file changed
not ok 5 - atime set correctly

#   Failed test 'atime set correctly'
#   at t/utime.t line 168.
#          got: '1'
#     expected: '1.111111111'
not ok 6 - mtime set correctly

#   Failed test 'mtime set correctly'
#   at t/utime.t line 170.
#          got: '2'
#     expected: '2.222222222'
#utime $filename round-trip
ok 7 - One file changed
ok 8 - One file changed
ok 9 - atime round trip ok
ok 10 - mtime round trip ok
utime $filename and $fh
ok 11 - Two files changed
not ok 12 - File 1 atime set correctly

#   Failed test 'File 1 atime set correctly'
#   at t/utime.t line 195.
#          got: '1'
#     expected: '1.111111111'
not ok 13 - File 1 mtime set correctly

#   Failed test 'File 1 mtime set correctly'
#   at t/utime.t line 197.
#          got: '2'
#     expected: '2.222222222'
not ok 14 - File 2 atime set correctly

#   Failed test 'File 2 atime set correctly'
#   at t/utime.t line 203.
#          got: '1'
#     expected: '1.111111111'
not ok 15 - File 2 mtime set correctly

#   Failed test 'File 2 mtime set correctly'
#   at t/utime.t line 205.
#          got: '2'
#     expected: '2.222222222'
# utime undef sets time to now
ok 16 - Two files changed
ok 17 - File 1 atime set correctly
ok 18 - File 1 mtime set correctly
ok 19 - File 2 atime set correctly
ok 20 - File 2 mtime set correctly
# negative atime dies
ok 21 - negative time error
# negative mtime dies;
ok 22 - negative time error
# Looks like you failed 8 tests of 22.
Dubious, test returned 8 (wstat 2048, 0x800)
Failed 8/22 subtests 

Test Summary Report
-------------------
../dist/Time-HiRes/t/utime.t (Wstat: 2048 (exited 8) Tests: 22 Failed: 8)
  Failed tests:  2-3, 5-6, 12-15
  Non-zero exit status: 8
Files=1, Tests=22,  1 wallclock secs ( 0.02 usr  0.01 sys +  0.22 cusr  0.03 csys =  0.28 CPU)
Result: FAIL
Finished test run at Thu Mar  6 13:54:43 2025.

It seems that the test code expected floats but got integers.

WRT the version of Debian I am running, I derived the version I reported in my post from the output of cat /proc/version, but the /etc/debian_version file contains 12.1. Hope that clarifies things.

Thanks again.

Mar 06, 2025 at 19:54 UTC

From your other comment you're using ext4, so I'd expect the file system to support sub-second timestamps, if you do:

# this is a command-line command, not perl code
stat .
[download]

does it show sub-second timestamps, eg. I get

$ stat .
  File: .
  Size: 20480           Blocks: 40         IO Block: 4096   directory
Device: 253,2   Inode: 33079540    Links: 26
Access: (0755/drwxr-xr-x)  Uid: ( 1000/    tony)   Gid: ( 1000/    ton
+y)
Access: 2025-03-10 07:39:22.352732987 +1100
Modify: 2025-03-06 15:07:42.145467132 +1100
Change: 2025-03-06 15:07:42.145467132 +1100
 Birth: 2022-08-08 15:04:51.515950529 +1000
[download]