Performance fixes

- Cache only supported on PX4. Solo sends param updates at a high rate
to update gimbal values. This was causing the cache to update itself at
too high of a rate, killing performance, especially on iOS.
- Fixed read/write index usage to provide correct progress bar updates

src/FactSystem/ParameterLoader.cc

@@ -47,6 +47,9 @@ ParameterLoader::ParameterLoader(Vehicle* vehicle)
     , _defaultComponentId(MAV_COMP_ID_ALL)
     , _parameterSetMajorVersion(-1)
     , _parameterMetaData(NULL)
+    , _prevWaitingReadParamIndexCount(0)
+    , _prevWaitingReadParamNameCount(0)
+    , _prevWaitingWriteParamNameCount(0)
     , _initialRequestRetryCount(0)
     , _totalParamCount(0)
 {
@@ -90,14 +93,26 @@ void ParameterLoader::_parameterUpdate(int uasId, int componentId, QString param
 
     _initialRequestTimeoutTimer.stop();
 
-    qCDebug(ParameterLoaderLog) << "_parameterUpdate (usaId:" << uasId <<
-                                    "componentId:" << componentId <<
-                                    "name:" << parameterName <<
-                                    "count:" << parameterCount <<
-                                    "index:" << parameterId <<
-                                    "mavType:" << mavType <<
-                                    "value:" << value <<
-                                    ")";
+    if (_initialLoadComplete) {
+        qCDebug(ParameterLoaderLog) << "_parameterUpdate (id:" << uasId <<
+                                        "componentId:" << componentId <<
+                                        "name:" << parameterName <<
+                                        "count:" << parameterCount <<
+                                        "index:" << parameterId <<
+                                        "mavType:" << mavType <<
+                                        "value:" << value <<
+                                        ")";
+    } else {
+        // This is too noisy during initial load
+        qCDebug(ParameterLoaderVerboseLog) << "_parameterUpdate (id:" << uasId <<
+                                       "componentId:" << componentId <<
+                                       "name:" << parameterName <<
+                                       "count:" << parameterCount <<
+                                       "index:" << parameterId <<
+                                       "mavType:" << mavType <<
+                                       "value:" << value <<
+                                       ")";
+    }
 
 #if 0
     // Handy for testing retry logic
@@ -115,7 +130,7 @@ void ParameterLoader::_parameterUpdate(int uasId, int componentId, QString param
     }
 #endif
 
-    if (parameterName == "_HASH_CHECK") {
+    if (_vehicle->px4Firmware() && parameterName == "_HASH_CHECK") {
         /* we received a cache hash, potentially load from cache */
         _tryCacheHashLoad(uasId, componentId, value);
         return;
@@ -201,20 +216,25 @@ void ParameterLoader::_parameterUpdate(int uasId, int componentId, QString param
         qCDebug(ParameterLoaderLog) << "waitingWriteParamNameCount:" << waitingWriteParamNameCount;
     }
 
-    int waitingParamCount = waitingReadParamIndexCount + waitingReadParamNameCount + waitingWriteParamNameCount;
-    if (waitingParamCount) {
-        qCDebug(ParameterLoaderLog) << "waitingParamCount:" << waitingParamCount;
+    int readWaitingParamCount = waitingReadParamIndexCount + waitingReadParamNameCount;
+    int totalWaitingParamCount = readWaitingParamCount + waitingWriteParamNameCount;
+    if (totalWaitingParamCount) {
+        qCDebug(ParameterLoaderLog) << "totalWaitingParamCount:" << totalWaitingParamCount;
     } else if (_defaultComponentId != MAV_COMP_ID_ALL) {
         // No more parameters to wait for, stop the timeout. Be careful to not stop timer if we don't have the default
         // component yet.
         _waitingParamTimeoutTimer.stop();
     }
 
-    // Update progress bar
-    if (waitingParamCount == 0) {
-        emit parameterListProgress(0);
+    // Update progress bar for waiting reads
+    if (readWaitingParamCount == 0) {
+        // We are no longer waiting for any reads to complete
+        if (_prevWaitingReadParamIndexCount + _prevWaitingReadParamNameCount != 0) {
+            // Set progress to 0 if not already there
+            emit parameterListProgress(0);
+        }
     } else {
-        emit parameterListProgress((float)(_totalParamCount - waitingParamCount) / (float)_totalParamCount);
+        emit parameterListProgress((float)(_totalParamCount - readWaitingParamCount) / (float)_totalParamCount);
     }
 
     // Get parameter set version
@@ -286,12 +306,25 @@ void ParameterLoader::_parameterUpdate(int uasId, int componentId, QString param
         _setupGroupMap();
     }
 
-    if (waitingParamCount == 0) {
-        // Now that we know vehicle is up to date persist
+    if (_prevWaitingWriteParamNameCount != 0 &&  waitingWriteParamNameCount == 0) {
+        // If all the writes just finished the vehicle is up to date, so persist.
         _saveToEEPROM();
-        _writeLocalParamCache(uasId, componentId);
     }
 
+    // Update param cache. The param cache is only used on PX4 Firmware since ArduPilot and Solo have volatile params
+    // which invalidate the cache. The Solo also streams param updates in flight for things like gimbal values
+    // which in turn causes a perf problem with all the param cache updates.
+    if (_vehicle->px4Firmware()) {
+        if (_prevWaitingReadParamIndexCount + _prevWaitingReadParamNameCount != 0 && readWaitingParamCount == 0) {
+            // All reads just finished, update the cache
+            _writeLocalParamCache(uasId, componentId);
+        }
+    }
+
+    _prevWaitingReadParamIndexCount = waitingReadParamIndexCount;
+    _prevWaitingReadParamNameCount = waitingReadParamNameCount;
+    _prevWaitingWriteParamNameCount = waitingWriteParamNameCount;
+
     // Don't fail initial load complete if default component isn't found yet. That will be handled in wait timeout check.
     _checkInitialLoadComplete(false /* failIfNoDefaultComponent */);
 }
@@ -955,8 +988,10 @@ void ParameterLoader::_checkInitialLoadComplete(bool failIfNoDefaultComponent)
                               "This will cause QGroundControl to be unable to display its full user interface. "
                               "If you are using modified firmware, you may need to resolve any vehicle startup errors to resolve the issue. "
                               "If you are using standard firmware, you may need to upgrade to a newer version to resolve the issue.");
-        qCWarning(ParameterLoaderLog) << "The following parameter indices could not be loaded after the maximum number of retries: " << indexList;
-        emit parametersReady(true);
+        if (!qgcApp()->runningUnitTests()) {
+            qCWarning(ParameterLoaderLog) << "The following parameter indices could not be loaded after the maximum number of retries: " << indexList;
+        }
+        emit parametersReady(true /* missingParameters */);
         return;
     }
 
@@ -966,15 +1001,17 @@ void ParameterLoader::_checkInitialLoadComplete(bool failIfNoDefaultComponent)
                               "This will cause QGroundControl to be unable to display its full user interface. "
                               "If you are using modified firmware, you may need to resolve any vehicle startup errors to resolve the issue. "
                               "If you are using standard firmware, you may need to upgrade to a newer version to resolve the issue.");
-        qCWarning(ParameterLoaderLog) << "Default component was never found, param:" << _defaultComponentIdParam;
-        emit parametersReady(true);
+        if (!qgcApp()->runningUnitTests()) {
+            qCWarning(ParameterLoaderLog) << "Default component was never found, param:" << _defaultComponentIdParam;
+        }
+        emit parametersReady(true /* missingParameters */);
         return;
     }
 
     // No failures, signal good load
     _parametersReady = true;
     _determineDefaultComponentId();
-    emit parametersReady(false);
+    emit parametersReady(false /* no missingParameters */);
 }
 
 void ParameterLoader::_initialRequestTimeout(void)

src/FactSystem/ParameterLoader.h

@@ -151,7 +151,13 @@ private:
     int         _parameterSetMajorVersion;      ///< Version for parameter set, -1 if not known
     QObject*    _parameterMetaData;             ///< Opaque data from FirmwarePlugin::loadParameterMetaDataCall
 
-    static const int _maxInitialRequestListRetry = 5;       ///< Maximum retries for request list
+    // Wait counts from previous parameter update cycle
+    int         _prevWaitingReadParamIndexCount;
+    int         _prevWaitingReadParamNameCount;
+    int         _prevWaitingWriteParamNameCount;
+
+
+    static const int _maxInitialRequestListRetry = 4;       ///< Maximum retries for request list
     int              _initialRequestRetryCount;             ///< Current retry count for request list
     static const int _maxInitialLoadRetrySingleParam = 10;  ///< Maximum retries for initial index based load of a single param
     static const int _maxReadWriteRetry = 5;                ///< Maximum retries read/write