presto-main/src/main/java/io/prestosql/execution/resourcegroups/ResourceUsage.java/ResourceUsage/subtract
class ResourceUsage:    public ResourceUsage subtract(ResourceUsage other)
    {
        long newCpuUsageMillis = saturatedSubtract(this.cpuUsageMillis, other.cpuUsageMillis);
        long newMemoryUsageBytes = saturatedSubtract(this.memoryUsageBytes, other.memoryUsageBytes);
        return new ResourceUsage(newCpuUsageMillis, newMemoryUsageBytes);
    }