This reliably crashes J for me.
metcon=: {{
lock=: 10 T. 0
sleep=: 6!:3
task=. {{
echo 'Task ',y,&":' waiting...'
11 T. lock;_ NB. wait
sleep 2
echo r=.'Task ',y,&":' has the semaphore'
13 T. lock NB. release
r rplc 'has';'had'
}}
0&T.@'' each i.0>.4-1 T.'' NB. ensure at least four threads
echo (":1 T. ''),' threads'
r=. > task f. t.''"0 i.10 NB. dispatch and wait for 10 tasks
14 T. lock NB. discard lock
r
}}
metcon''
Sometimes I even get a popup, like:
---------------------
jqt.exe - Application Error
The instruction at 0x00007FF85D0007F4 referenced memory at
0x0000000000000064. The memory could not be read.
Click on OK to terminate the program.
[OK]
---------------------
Replacing 11 T. lock;_ with 11 T. lock is nice (but it still crashes).
FYI,
--
Raul
On Wed, Jun 1, 2022 at 7:02 PM Elijah Stone <[email protected]> wrote:
>
> In the mean time, you can work around the issue by using task f..
>
> On Wed, 1 Jun 2022, Raul Miller wrote:
>
> > Oops, bad copy and paste
> >
> > Ignore the first (incomplete) declaration of metcon.
> >
> > Actually, please treat the declaration at
> > http://www.jsoftware.com/pipermail/beta/2022-June/010566.html as
> > canonical for this issue.
> >
> > Thanks,
> >
> > --
> > Raul
> >
> > On Wed, Jun 1, 2022 at 3:57 PM Raul Miller <[email protected]> wrote:
> >>
> >> https://www.rosettacode.org/wiki/Metered_concurrency
> >>
> >> I wanted to put together a more serious J implementation of the
> >> rosettacode metered concurrency task.
> >>
> >> Unfortunately, either (a) I do not understand how the threading
> >> primitives are supposed to work, or (b) they are not working properly.
> >>
> >> metcon=: {{
> >> lock=: 10 T. 0
> >> sleep=: 6!:3
> >> metcon=: {{
> >> lock=: 10 T. 0
> >> sleep=: 6!:3
> >> task=. {{
> >> 11 T. lock;_ NB. wait
> >> sleep 2
> >> echo r=.'Task ',y,&":' has the semaphore'
> >> 13 T. lock NB. release
> >> r rplc 'has';'had'
> >> }}
> >> 0&T.@'' each i.0>4-1 T.'' NB. ensure at least four threads
> >> r=. task t.''"0 i.10 NB. dispatch 10 tasks
> >> #each r NB. wait for completion
> >> 14 T. lock NB. discard lock
> >> r
> >> }}
> >> I expect this to take about 20 seconds (because of the use of 6!:3)
> >> and run ten tasks in 3 of the four guaranteed threads.
> >>
> >> Instead, what I get is this:
> >>
> >> metcon''
> >> Task 1 has the semaphore
> >> Task 3 has the semaphore
> >> Task 5 has the semaphore
> >> Task 7 has the semaphore
> >> Task 9 has the semaphore
> >> |value error
> >> | #each r
> >>
> >> So it looks like half of my tasks are getting lost somewhere, and it
> >> looks like all of the results from those tasks are getting lost
> >> somewhere.
> >>
> >> JVERSION
> >> Engine: j904/j64avx2/windows
> >> Beta-d: commercial/2022-05-19T20:39:35
> >> Library: 9.04.01
> >> Qt IDE: 2.0.3/6.2.4(6.2.4)
> >> Platform: Win 64
> >> Installer: J904 install
> >> InstallPath: c:/other/j904
> >> Contact: www.jsoftware.com
> >>
> >> Thanks,
> >>
> >> --
> >> Raul
> > ----------------------------------------------------------------------
> > For information about J forums see http://www.jsoftware.com/forums.htm
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
