[cfarm-users] Does cfarm421 need more RAM?

[Jacob Bachmeyer]

Martin Guy via cfarm-users wrote:
> Il 27/03/24 08:48, Pierre Muller via cfarm-users ha scritto:
>
>> [...]
>>   Test tw2494 is specifically a test that checks what is happening
>> if the program tries to allocate 4096 Tb (=2Gb*2Gb).
>
>
> I was going to say "Give it some swap space?" but that seems so 
> obvious to be fatuous, however, I wonder if the system running out of 
> VM might affect other processes on the same machine.
>
> Pierre, can you obtain the same effect by using ulimit?

The system is not running out of VM at all.  It is rejecting 
outrageously large allocations, as it is expected to do.  If I read the 
above correctly, there is a test that expects to cause the system to 
return ENOMEM by asking "for the moon"---a large multiple of the total 
space available on any currently-reasonable machine.

Adjusting the tests to use ulimit and an otherwise-satisfiable 
allocation would likely work, but would limit the portability of the 
tests, as not all systems have ulimit.  DOS, for example, most certainly 
does not.

Pierre's current solution will work until someone actually has a machine 
with about 4 PB of RAM.


-- Jacob