Allow the refresh interval to be adjusted in dynamic intensity with a --gpu-dyninterval parameter.

README

@@ -173,6 +173,7 @@ GPU only options:
 --device|-d <arg>   Select device to use, (Use repeat -d for multiple devices, default: all)
 --disable-gpu|-G    Disable GPU mining even if suitable devices exist
 --gpu-threads|-g <arg> Number of threads per GPU (1 - 10) (default: 2)
+--gpu-dyninterval <arg> Set the refresh interval in ms for GPUs using dynamic intensity (default: 7)
 --gpu-engine <arg>  GPU engine (over)clock range in Mhz - one value, range and/or comma separated list (e.g. 850-900,900,750-850)
 --gpu-fan <arg>     GPU fan percentage range - one value, range and/or comma separated list (e.g. 25-85,85,65)
 --gpu-memclock <arg> Set the GPU memory (over)clock in Mhz - one value for all or separate by commas for per card.

cgminer.c

@@ -100,6 +100,7 @@ int opt_bench_algo = -1;
 static const bool opt_time = true;
 
 #ifdef HAVE_OPENCL
+int opt_dynamic_interval = 7;
 static bool opt_restart = true;
 static bool opt_nogpu;
 #endif
@@ -674,6 +675,9 @@ static struct opt_table opt_config_table[] = {
 			opt_set_bool, &opt_fail_only,
 			"Don't leak work to backup pools when primary pool is lagging"),
 #ifdef HAVE_OPENCL
+	OPT_WITH_ARG("--gpu-dyninterval",
+		     set_int_1_to_65535, opt_show_intval, &opt_dynamic_interval,
+		     "Set the refresh interval in ms for GPUs using dynamic intensity"),
 	OPT_WITH_ARG("--gpu-platform",
 		     set_int_0_to_9999, opt_show_intval, &opt_platform_id,
 		     "Select OpenCL platform ID to use for GPU mining"),

device-gpu.c

@@ -1176,6 +1176,8 @@ static bool opencl_prepare_work(struct thr_info __maybe_unused *thr, struct work
 	return true;
 }
 
+extern int opt_dynamic_interval;
+
 static uint64_t opencl_scanhash(struct thr_info *thr, struct work *work,
 				uint64_t __maybe_unused max_nonce)
 {
@@ -1209,10 +1211,10 @@ static uint64_t opencl_scanhash(struct thr_info *thr, struct work *work,
 		/* Try to not let the GPU be out for longer than 6ms, but
 		 * increase intensity when the system is idle, unless
 		 * dynamic is disabled. */
-		if (gpu_ms_average > 7) {
+		if (gpu_ms_average > opt_dynamic_interval) {
 			if (gpu->intensity > MIN_INTENSITY)
 				--gpu->intensity;
-		} else if (gpu_ms_average < 3) {
+		} else if (gpu_ms_average < ((opt_dynamic_interval / 2) ? : 1)) {
 			if (gpu->intensity < MAX_INTENSITY)
 				++gpu->intensity;
 		}