[Mageia-dev] make -l ?

[Colin Guthrie]

'Twas brillig, and Pascal Terjan at 03/09/12 00:18 did gyre and gimble:
> On Sun, Sep 2, 2012 at 5:14 PM, Jose Jorge <lists.jjorge at free.fr> wrote:
>> Le 31/08/2012 11:40, Pascal Terjan a écrit :
>>
>>> Currently %make is expanded to make -j<nb cpu>
>>>
>>> I'd like it to be replaced with make -l<nb cpu>
>>>
>>>
>> Some activities, like USB transfers are seen as huge system load (I often
>> get more than 4 on a monocpu system, while is CPU is idle to compile. So I
>> think we may end with a side effect that build time will be longer....
> 
> Currently I see the following cases:
> - 1 big job with parallel makefile (like kernel), it will probably run
> more builds in parallel as building 24 .o does not cause a load of 24
> - 2 big jobs with parallel makefile, it will probably reduce things as
> currently each of them run 24 builds in parallel, leading to a load of
> about 40, now the load will be 24
> - 1 big job and a small one: I am not sure there will be much change
> - 1 or 2 small jobs: no change
> 
> And yes the load is not only the cpu, but that's a good thing. If we
> have 40 processes trashing the disk it's better to not start more even
> if we have 20 cpu idling
> 
> But yes it needs to be tested

And of course in the context of the BS, the IO load will not be
artificially high from USB type transfers so it will probably be "real" IO.

Col


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Colin Guthrie
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