Yeah, it really does thrash the SSD. That is why I switched to running off of a ramdisk that syncs to disk on shutdown/reboot. It definitely cut down the writing to my SSD a lot.

Somewhere around here I've seen an app_config setting to run more than 1 wu at a time.
At first glance I think my Radeon VII is underutilized with 1 wu. The load constantly jumps from 1% - 99% like a yo-yo. Run times are also pretty random. 1:44 - 2:50 min with my cpu set to 50% usage. When I was running it at 93% cpu usage (16 core 3950X) the run times were over 4min. This project must need a few spare CPU threads to run the best times.
I guess like all projects, it takes a bit of juggling to set the cpu/gpu ratio.

<app_config>
 	<app>
 		<name>opng</name>
 		<gpu_versions>
			<gpu_usage>0.33</gpu_usage>
			<cpu_usage>1</cpu_usage>
		</gpu_versions>
 	</app>
 	<app_version>
 		<app_name>opng</app_name>
 		<plan_class>opencl_intel_gpu_102</plan_class>
 		<ngpus>1</ngpus>
 	</app_version>
 	<report_results_immediately/>
 </app_config>