Also try to gradually reduce spark.executor.memory You need to allocate less memory to the JVM heap because the GPU needs a large chunk of the node's off-heap (system) memory. The GPU memory is allocated outside the JVM heap. If the heap is too large, it crowds out the native memory required by RAPIDS/CUDA.

Again reduce gradually 

spark.rapids.memory.gpu.allocFraction from the default (usually 0.5 or 0.8). Try 0.4 or 0.3