Agreed

Sent from my iPad

> On 8 Feb 2021, at 05:55, Raul Miller <[email protected]> wrote:
> 
> Actually, ... the numbers I was seeing suggested somewhat over 36GB
> would be used. But the OS needs some memory also, and there wasn't any
> benefit that I could see in being overly accurate, so I rounded that
> to "about 40GB"
> 
> FYI,
> 
> -- 
> Raul
> 
> On Sun, Feb 7, 2021 at 3:04 PM 'Michael Day' via General
> <[email protected]> wrote:
>> 
>> I don't think your problem was the spec of your pc,  although 8GB is
>> pretty good.
>> 
>> Mine, with 16GB RAM,  got stuck with taking all triples, seeming to need
>> ~38GB,
>> and Raul's analysis also suggests 40GB .
>> 
>> Cheers,
>> 
>> Mike
>> 
>>> On 07/02/2021 17:05, Francesco Pedulla' wrote:
>>> Thanks to all that answered so quickly. In particular:
>>> @Brian: yes, I was aware that a smaller case would work
>>> @R.E.: your suggestion to skip the boxing seems to avoid the issue
>>> altogether (see working code below)
>>> @Michael: congrats for reading my code so well - in fact, I messed it up
>>> while producing a slimmed down version to share; w.r.t. boxing, see my
>>> answer to R.E.
>>> 
>>> Now the fixed code reads
>>> 
>>> 
>>> perm =: i.@! A. i.
>>> 
>>> base10 =: 10&base
>>> 
>>> PanDigS =: (perm 10) from i.10
>>> 
>>> PanDigT =: 3 base10\"1 PanDigS
>>> 
>>> 
>>> It does not break anymore (logical correctness is another story).
>>> 
>>> 
>>> The fact that the new code completes without errors suggests that the issue
>>> lies with the boxing operation. It could be either directly or indirectly,
>>> e.g. by stressing the operating system memory management code (paging?).
>>> Should someone investigate, I add that my machine is an old HP 280 with a
>>> dual core Celeron CPU [email protected] and 8GB of RAM.
>>> 
>>> 
>>> Best regards,
>>> 
>>> 
>>> Francesco
>>> 
>>> ---------- Forwarded message ---------
>>> From: Francesco Pedulla' <[email protected]>
>>> Date: Sun, Feb 7, 2021 at 12:32 PM
>>> Subject: Bug in J807/J902
>>> To: <[email protected]>
>>> 
>>> 
>>> The following piece of code does not work on Ubuntu 20.04.
>>> 
>>> load 'primitives'
>>> 
>>> perm =: i.@! A. i.
>>> 
>>> PanDigS =: (perm 10) from (1 + i.10)
>>> 
>>> PanDigT =: 10 base"1 each 3 box\"1 PanDigS
>>> 
>>> 
>>> The effect is variable: crash of the J interpreter, freeze of the Qt
>>> interface or even of the whole system. It shows up both on J807 and J902.
>>> 
>>> The dataset is quite large:
>>> 
>>> 
>>> 7!:5 <'PanDigS'
>>> 
>>> 5.36871e8
>>> 
>>> 
>>> and the process crashes (or the system freezes) after several seconds.
>>> Hence, I suspect an issue with memory management.
>>> 
>>> Any idea or suggestion on how to bypass the problem?
>>> 
>>> Thanks,
>>> 
>>> 
>>> Francesco
>>> ----------------------------------------------------------------------
>>> For information about J forums see http://www.jsoftware.com/forums.htm
>> 
>> 
>> --
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