Using custom KeyToHash in configuration resulting in drop of cache hit ratio

@muskan_sethia If your srcDest.DestinationCellID and srcDest.SourceCellID are uint32, you can do something like

KeyToHash: func(key interface{}) (uint64, uint64) {
			srcDest, _ := key.(models.SourceDestinationCellID)
			return uint64(srcDest.DestinationCellID) << 32 | uint64(srcDest.SourceCellID), 0
		}

But this is based on an assumption that your (DestinationCellID, SourceCellID) is unique.