Random values from NVML functions

[Ty Young]

On 5/13/20 6:38 PM, Maurizio Cimadamore wrote:
> Hi,
> is this a regression? E.g. did this work before and now it started 
> behave differently all of a sudden (e.g. after a rebuild on panama) or 
> is this a new function you are trying to call and you are getting an 
> odd behavior?


Not sure.


After converting everything to FMA from pointer it started giving me 0 
for everything where the Pointer API would give me seemingly correct 
non-zero values the majority of the time, but would sometimes give 
random garbage. Because the old Pointer API never zero'd memory I have 
no idea if those values were valid or not, so I didn't think much of 
always getting 0.


Yesterday I did some cleanups in the OO code(layer under JavaFX), 
including converting NativeValue<Integer> instances to 
NativeInteger(same for longlong) and it started doing this, which I 
think is partially correct: if I start a GPU benchmarking 
application(Unigine Superposition) and view the processes content in the 
GUI, I do see seemingly correct utilization rates that match in-app 
On-Screen-Display FPS.


The issue is with Memory Utilization and Video encoder/decoder Utilization.


>
> Maurizio
>
> On 14/05/2020 00:00, Ty Young wrote:
>> Hi,
>>
>>
>> Currently I'm getting random values[1] from this NVML function[2]. 
>> I've spent a few hours dumping sizes and re-checking my abstraction 
>> layer code in order to figure out why it's doing this but am not 
>> seeing anything. I'm wondering if there ware any recent bug fixes in 
>> FMA that might cause this that were fixed. If not I'm going to have 
>> to try asking on the Nvidia forums.
>>
>>
>> For reference, the function binding can be found here:
>>
>>
>> https://github.com/BlueGoliath/java-nvidia-bindings/blob/master/modules/org.goliath.bindings.nvml/src/main/java/org/goliath/bindings/nvml/main/nvml_h.java#L426 
>>
>>
>>
>> and the abstraction layer here:
>>
>>
>> https://github.com/BlueGoliath/Crosspoint/tree/master/src/main/java/org/goliath/crosspoint 
>>
>>
>>
>> I'm able to read/write other structs just fine, such as:
>>
>>
>> https://github.com/BlueGoliath/java-nvidia-bindings/blob/master/modules/org.goliath.bindings.nvctrl/src/main/java/org/goliath/bindings/nvctrl/structs/NVCTRLAttributeValidValuesRec.java 
>>
>>
>>
>> and again, all byte sizes seem correct(48 bytes for the NVML struct), 
>> so I'm really lost here.
>>
>>
>>
>> [1] https://imgur.com/a/wrQtOXq
>>
>> [2] 
>> https://docs.nvidia.com/deploy/nvml-api/group__nvmlGridQueries.html#group__nvmlGridQueries_1gb0ea5236f5e69e63bf53684a11c233bd
>>