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[[!tag open_issue_porting]]

Neither the `time` executable from the GNU time package work completely
correctly, nor does the GNU Bash built-in one.

    tschwinge@flubber:~ $ \time sleep 2
    0.00user 0.00system 9:38:00elapsed 0%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+0outputs (0major+0minor)pagefaults 0swaps
    tschwinge@flubber:~ $ \time sleep 4
    0.00user 0.00system 18:50:25elapsed 0%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+0outputs (0major+0minor)pagefaults 0swaps
    tschwinge@flubber:~ $ \time sleep 6
    0.00user 0.00system 28:00:53elapsed 0%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+0outputs (0major+0minor)pagefaults 0swaps
    tschwinge@flubber:~ $ time sleep 2
    
    real    0m2.093s
    user    0m0.000s
    sys     0m0.011s
    tschwinge@flubber:~ $ time sleep 4
    
    real    0m4.083s
    user    0m0.000s
    sys     0m0.010s
    tschwinge@flubber:~ $ time sleep 6
    
    real    0m6.164s
    user    0m0.000s
    sys     0m0.010s

GNU time's *elapsed* value is off by some factor.

    $ \time factor 1111111111111111111
    1111111111111111111: 1111111111111111111
    0.00user 0.00system 52:39:24elapsed 0%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+0outputs (0major+0minor)pagefaults 0swaps
    $ time factor 1111111111111111111
    1111111111111111111: 1111111111111111111
    
    real    0m11.424s
    user    0m0.000s
    sys     0m0.010s

As above; also here all the running time should be attriuted to *user* time.
This is probably a [[!taglink open_issue_gnumach]].


# 2011-09-02

Might want to revisit this, and take Xen [[!tag open_issue_xen]] into account
-- I believe flubber has already been Xenified at that time.


## IRC, freenode, #hurd, 2011-09-02

While testing some [[performance/IPC_virtual_copy]] performance issues:

    <tschwinge> And I can confirm that with dd if=/dev/zero of=/dev/null bs=4k
      running, a parallel sleep 10 takes about 20 s (on strauss).


# IRC, OFTC, #debian-hurd, 2013-03-30

    <clopez>  /usr/bin/time seems broken on hurd. It reports weird things.  Ex:
    <clopez> # /usr/bin/time sleep 1
    <clopez> 0.00user 0.00system 4:37:46elapsed 0%CPU (0avgtext+0avgdata
      0maxresident)k
    <clopez> 0inputs+0outputs (0major+0minor)pagefaults 0swaps
    <pinotree> o_O
    <pinotree> indeed, let's see what that time does
    <pinotree> seems like only the elapsed time, %E
    <clopez> not only the time, but also the other variables (pagefaults, cpu
      used, etc) are wrong. For example compare the output of
    <clopez>  /usr/bin/time openssl speed ecdhp521
    <clopez> on linux and hurd
    <pinotree> most probably they are not implemented yet
    <pinotree> they are all 0
    <clopez> yes
    <clopez> should i report a bug to pkg time?
    <pinotree> not sure
    <pinotree> at least, there's this difference between eg amd64 and hurd-i386
      in configure's output:
    <pinotree> -checking for wait3 that fills in rusage... yes
    <pinotree> +checking for wait3 that fills in rusage... no
    <clopez> found this:
      https://www.gnu.org/software/hurd/open_issues/time.html
    <pinotree> seems related, yes
    <pinotree> clopez: apparently all the ways to get the HZ define, either
      directly or with CLOCKS_PER_SEC or CLK_TCK, so it gets defined as HZ
    <pinotree> ... as 60, i mean (instead of 1000000)
    <pinotree> $ ./time sleep 1
    <pinotree> 0.00user 0.00system 0:01.01elapsed 0PU (0avgtext+0avgdata
      0maxresident)k
    <pinotree> :)
    <clopez> what it was?
    <pinotree> i added the check for time.h, and included in the no-wait3 case
      in resuse.c
    <pinotree> (omg, the last release of gnu time was in 1997)
    <clopez> lol
    <pinotree> hm not yet fixed
    <pinotree> oh minor typo
    <pinotree> clopez: http://paste.debian.net/246004/
    <pinotree> i will update the wiki page (on the hurd site) and send the
      patch tomorrow
    <clopez> nice
    <pinotree> yw, thanks again
    <clopez> i dropped the patch on debian/patches of pkg time.. rebuilt it
      both on linux and hurd
    <clopez> and works as expected in both cases
    <clopez> i think you should forward the patch to the mantainer of pkg time
    <pinotree> is there anyone maintaining gnu time?
    <clopez> http://packages.qa.debian.org/t/time.html
    <clopez> Maintainers for time are Bob Proulx <bob@proulx.com>.
    <pinotree> that's the debian maintainer, yes, which is what i implied
      earlier with "send the patch"
    <clopez> i guess that filling a bug against time with this patch attached
      should be enough
    <pinotree> yeah
    <clopez> wow... not only you fixed the elapsed time but also the other
      variables :)
    <clopez>  /usr/bin/time openssl speed ecdhp521
    <clopez> now it reports cpu used and pagefaults :)
    <pinotree> does it?
    <clopez> 10.00user 0.01system 0:10.11elapsed 99%CPU (0avgtext+0avgdata
      0maxresident)k
    <clopez> 0inputs+0outputs (67major+656minor)pagefaults 0swaps


# IRC, OFTC, #debian-hurd, 2013-03-31

    <pinotree> clopez: #704283