-LotOfMem Switch, what's it for?

Message boards : Number crunching : -LotOfMem Switch, what's it for?
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CryptokiD
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Message 2016866 - Posted: 27 Oct 2019, 15:29:22 UTC

In the stderr output of a few ATI multibeam applications I see a reference to -LotOfMem used. Here is an example from this host: https://setiathome.berkeley.edu/result.php?resultid=8170505486

Used GPU device parameters are:
Number of compute units: 5
Single buffer allocation size: 128MB
Total device global memory: 2047MB
max WG size: 256
local mem type: Real
LotOfMem path: yes
LowPerformanceGPU path: no
HighPerformanceGPU path: no
period_iterations_num=50

I did search the forums and duckduckgo but I did not find the answers I seek, I'd like to know the details of what it does, why it's there, and maybe some example situations of when to use and not use it. Why it isn't documented in the readme's that Come with the relevant applications?
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Message 2016867 - Posted: 27 Oct 2019, 15:34:52 UTC - in response to Message 2016866.  

That is just an internal flag the science application uses to determine how to set up the card to crunch the FFT array. Nothing you have any control over.
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Message 2016885 - Posted: 27 Oct 2019, 19:16:26 UTC

if i put -lotofmem in the options file it changes lot of mem to yes in the stderr. am i under illusion because i never see lotofmem with a yes on my setup before now?
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Message 2016917 - Posted: 27 Oct 2019, 23:37:15 UTC - in response to Message 2016885.  

if i put -lotofmem in the options file it changes lot of mem to yes in the stderr. am i under illusion because i never see lotofmem with a yes on my setup before now?

You'll have to ask Raistmer, the developer whether that is a real user settable option parameter. I have never seen it documented anywhere. Surprised setting that option didn't cause a config error complaint in the Event Log.
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Message 2016919 - Posted: 27 Oct 2019, 23:41:20 UTC

Memory does not process any tasks.
It is just an information.
It is only helpful in conjunction with other flags like high perf for example.
But not usable for iGPU.


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Message 2017315 - Posted: 31 Oct 2019, 4:28:45 UTC - in response to Message 2016919.  

Hope Rasty sees this.
Meanwhile, Would you happen to have any more info on it such as what it is suppose to output when enabled? Perhaps an example of what it is used for would be great if that isn't asking too much of you.
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Message boards : Number crunching : -LotOfMem Switch, what's it for?


 
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