diff --git a/Sources/Backup/LocalBackup/OASettingsHelper.mm b/Sources/Backup/LocalBackup/OASettingsHelper.mm
index 3f6acbdace..60ae6609d7 100644
--- a/Sources/Backup/LocalBackup/OASettingsHelper.mm
+++ b/Sources/Backup/LocalBackup/OASettingsHelper.mm
@@ -70,6 +70,8 @@
 #import "OASearchHistorySettingsItem.h"
 #import "OATileSource.h"
 #import "OAPluginsHelper.h"
+#import "OABackupHelper.h"
+#import "OAOperationLog.h"
 
 #include <OsmAndCore/Map/IOnlineTileSources.h>
 #include <OsmAndCore/Map/OnlineTileSources.h>
@@ -90,6 +92,9 @@ @implementation OASettingsHelper
 {
     __weak OAImportSettingsViewController *_importDataVC;
     NSInteger _currentBackupVersion;
+
+    // COLLECT_LOCAL_DIAG: remove after cloud sync performance investigation.
+    OAOperationLog *_cloudSyncOperationLog;
 }
 
 + (OASettingsHelper *) sharedInstance
@@ -108,6 +113,7 @@ - (instancetype)init
     if (self)
     {
         _currentBackupVersion = kVersion;
+        _cloudSyncOperationLog = [[OAOperationLog alloc] initWithOperationName:@"cloudSyncSettings" debug:BACKUP_DEBUG_LOGS];
     }
     return self;
 }
@@ -224,12 +230,30 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
 
 - (NSArray<OASettingsItem *> *) getFilteredSettingsItems:(NSArray<OAExportSettingsType *> *)settingsTypes addProfiles:(BOOL)addProfiles doExport:(BOOL)doExport
 {
+    [_cloudSyncOperationLog startOperation:@"COLLECT_LOCAL_DIAG getFilteredSettingsItems"];
+    CFAbsoluteTime phaseStartTime = CFAbsoluteTimeGetCurrent();
     NSMutableDictionary<OAExportSettingsType *, NSArray *> *typesMap = [NSMutableDictionary new];
     [typesMap addEntriesFromDictionary:[self getSettingsItems:addProfiles]];
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG getSettingsItems END duration=%.3f ms",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000]];
+
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     [typesMap addEntriesFromDictionary:[self getMyPlacesItems:NO]];
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG getMyPlacesItems END duration=%.3f ms",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000]];
+
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     [typesMap addEntriesFromDictionary:[self getResourcesItems]];
-    
-    return [self getFilteredSettingsItems:typesMap settingsTypes:settingsTypes settingsItems:@[] doExport:doExport];
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG getResourcesItems END duration=%.3f ms",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000]];
+
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
+    NSArray<OASettingsItem *> *result = [self getFilteredSettingsItems:typesMap settingsTypes:settingsTypes settingsItems:@[] doExport:doExport];
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG prepareFilteredItems END duration=%.3f ms count=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 result.count]];
+    [_cloudSyncOperationLog finishOperation:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG items=%ld", result.count]];
+    return result;
 }
 
 - (NSArray<OASettingsItem *> *) getFilteredSettingsItems:(NSDictionary<OAExportSettingsType *, NSArray *> *)allSettingsMap
@@ -243,7 +267,14 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         NSArray *settingsDataObjects = allSettingsMap[settingsType];
         if (settingsDataObjects != nil)
         {
-            [filteredSettingsItems addObjectsFromArray:[self prepareSettingsItems:settingsDataObjects settingsItems:settingsItems doExport:doExport]];
+            CFAbsoluteTime typeStartTime = CFAbsoluteTimeGetCurrent();
+            NSArray<OASettingsItem *> *preparedItems = [self prepareSettingsItems:settingsDataObjects settingsItems:settingsItems doExport:doExport];
+            [filteredSettingsItems addObjectsFromArray:preparedItems];
+            [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG prepareSettingsItems type=%@ duration=%.3f ms input=%ld output=%ld",
+                                         settingsType.name,
+                                         (CFAbsoluteTimeGetCurrent() - typeStartTime) * 1000,
+                                         settingsDataObjects.count,
+                                         preparedItems.count]];
         }
     }
     return filteredSettingsItems;
@@ -269,6 +300,8 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
 
 - (NSDictionary<OAExportSettingsType *, NSArray *> *) getSettingsItems:(BOOL)addProfiles
 {
+    CFAbsoluteTime methodStartTime = CFAbsoluteTimeGetCurrent();
+    CFAbsoluteTime phaseStartTime = methodStartTime;
     MutableOrderedDictionary<OAExportSettingsType *, NSArray *> *settingsItems = [MutableOrderedDictionary new];
     
     if (addProfiles)
@@ -281,7 +314,10 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         settingsItems[OAExportSettingsType.PROFILE] = appModeBeans;
     }
     settingsItems[OAExportSettingsType.GLOBAL] = @[[[OAGlobalSettingsItem alloc] init]];
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG settings profiles/global duration=%.3f ms",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000]];
 
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     OAMapButtonsHelper *buttonsHelper = [OAMapButtonsHelper sharedInstance];
     NSArray<QuickActionButtonState *> *buttonStates = [buttonsHelper getButtonsStates];
     if (buttonStates.count == 1)
@@ -297,7 +333,11 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
     NSArray<QuickActionButtonState *> *actionsList = [registry getButtonsStates];
     if (actionsList.count > 0)
         settingsItems[OAExportSettingsType.QUICK_ACTIONS] = actionsList;
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG settings quickActions duration=%.3f ms count=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 actionsList.count]];
     
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     NSArray<OAPOIUIFilter *> *poiList = [OAPOIFiltersHelper.sharedInstance getUserDefinedPoiFilters:NO];
     if (poiList.count > 0)
         settingsItems[OAExportSettingsType.POI_TYPES] = poiList;
@@ -305,7 +345,12 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
     NSArray<OAAvoidRoadInfo *> *impassableRoads = OAAvoidSpecificRoads.instance.getImpassableRoads;
     if (impassableRoads.count > 0)
         settingsItems[OAExportSettingsType.AVOID_ROADS] = impassableRoads;
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG settings poi/avoidRoads duration=%.3f ms poi=%ld roads=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 poiList.count,
+                                 impassableRoads.count]];
 
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     NSFileManager *fileManager = NSFileManager.defaultManager;
     BOOL isDir = NO;
     NSString *colorPaletteFolder = [OsmAndApp instance].colorsPalettePath;
@@ -345,17 +390,27 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         }
     }
 
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG settings colorPalette duration=%.3f ms",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000]];
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG settings TOTAL duration=%.3f ms",
+                                 (CFAbsoluteTimeGetCurrent() - methodStartTime) * 1000]];
     return settingsItems;
 }
 
 - (NSDictionary<OAExportSettingsType *, NSArray *> *)getMyPlacesItems:(BOOL)sorted
 {
+    CFAbsoluteTime methodStartTime = CFAbsoluteTimeGetCurrent();
+    CFAbsoluteTime phaseStartTime = methodStartTime;
     MutableOrderedDictionary<OAExportSettingsType *, NSArray *> *myPlacesItems = [MutableOrderedDictionary new];
     
     NSArray<OAFavoriteGroup *> *favoriteGroups = [OAFavoritesHelper getFavoriteGroups];
     if (favoriteGroups.count > 0)
         myPlacesItems[OAExportSettingsType.FAVORITES] = favoriteGroups;
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG myPlaces favorites duration=%.3f ms count=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 favoriteGroups.count]];
     
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     NSFileManager *fileManager = NSFileManager.defaultManager;
     NSArray<OASGpxDataItem *> *gpsDataItems;
     if (sorted)
@@ -384,7 +439,11 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         if (files.count > 0)
             myPlacesItems[OAExportSettingsType.TRACKS] = files;
     }
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG myPlaces tracks duration=%.3f ms count=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 gpsDataItems.count]];
     
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     OAOsmEditingPlugin *osmEditingPlugin = (OAOsmEditingPlugin *) [OAPluginsHelper getPlugin:OAOsmEditingPlugin.class];
     if (osmEditingPlugin)
     {
@@ -395,6 +454,9 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         if (editsPointList.count > 0)
             myPlacesItems[OAExportSettingsType.OSM_EDITS] = editsPointList;
     }
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG myPlaces osm duration=%.3f ms enabled=%d",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 osmEditingPlugin != nil]];
     // TODO: implement after adding Audio/video notes
 //    AudioVideoNotesPlugin plugin = OsmandPlugin.getPlugin(AudioVideoNotesPlugin.class);
 //    if (plugin != null) {
@@ -409,6 +471,7 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
 //            myPlacesItems.put(ExportSettingsType.MULTIMEDIA_NOTES, files);
 //        }
 //    }
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     NSArray<OADestination *> *mapMarkers = [OADestinationsHelper.instance sortedDestinationsWithoutParking];
     if (mapMarkers.count > 0)
     {
@@ -437,12 +500,22 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
     NSArray<OAHistoryItem *> *navigationHistoryEntries = [historyHelper getPointsFromNavigation:0];
     if (navigationHistoryEntries.count > 0)
         myPlacesItems[OAExportSettingsType.NAVIGATION_HISTORY] = navigationHistoryEntries;
-    
+
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG myPlaces markers/history duration=%.3f ms markers=%ld history=%ld/%ld/%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 mapMarkers.count,
+                                 markersHistory.count,
+                                 searchHistoryEntries.count,
+                                 navigationHistoryEntries.count]];
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG myPlaces TOTAL duration=%.3f ms",
+                                 (CFAbsoluteTimeGetCurrent() - methodStartTime) * 1000]];
     return myPlacesItems;
 }
 
 - (NSDictionary<OAExportSettingsType *, NSArray *> *)getResourcesItems
 {
+    CFAbsoluteTime methodStartTime = CFAbsoluteTimeGetCurrent();
+    CFAbsoluteTime phaseStartTime = methodStartTime;
     MutableOrderedDictionary<OAExportSettingsType *, NSArray *> *resourcesItems = [MutableOrderedDictionary new];
     
     NSArray<NSString *> *mapStyleFiles = [OARendererRegistry getPathExternalRenderers];
@@ -465,11 +538,14 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         if (items.count > 0)
             resourcesItems[OAExportSettingsType.CUSTOM_ROUTING] = items;
     }
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG resources renderers/routing duration=%.3f ms",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000]];
 //    List<OnlineRoutingEngine> onlineRoutingEngines = app.getOnlineRoutingHelper().getEngines();
 //    if (!Algorithms.isEmpty(onlineRoutingEngines)) {
 //        resourcesItems.put(ExportSettingsType.ONLINE_ROUTING_ENGINES, onlineRoutingEngines);
 //    }
     // TODO: implement export!
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     NSMutableArray<OATileSource *> *tileSources = [NSMutableArray new];
     NSArray<OAResourceItem *> *tileResources = [OAResourcesUIHelper getSortedRasterMapSources:YES];
     for (OAResourceItem *res in tileResources)
@@ -492,7 +568,12 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
     }
     if (tileSources.count > 0)
         resourcesItems[OAExportSettingsType.MAP_SOURCES] = tileSources;
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG resources rasterSources duration=%.3f ms resources=%ld sources=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 tileResources.count,
+                                 tileSources.count]];
     
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     QSet<OsmAnd::ResourcesManager::ResourceType> types;
     types << OsmAnd::ResourcesManager::ResourceType::MapRegion;
     NSArray<NSString *> *localIndexFiles = [OAResourcesUIHelper getInstalledResourcePathsByTypes:types includeHidden:NO];
@@ -503,7 +584,11 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         }];
         resourcesItems[OAExportSettingsType.STANDARD_MAPS] = sortedFiles;
     }
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG resources standardMaps duration=%.3f ms count=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 localIndexFiles.count]];
     
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     QSet<OsmAnd::ResourcesManager::ResourceType> wikiTypes;
     wikiTypes << OsmAnd::ResourcesManager::ResourceType::WikiMapRegion;
     wikiTypes << OsmAnd::ResourcesManager::ResourceType::Travel;
@@ -515,7 +600,11 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         }];
         resourcesItems[OAExportSettingsType.WIKI_AND_TRAVEL] = sortedFiles;
     }
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG resources wikiTravel duration=%.3f ms count=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 wikiFiles.count]];
 
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     QSet<OsmAnd::ResourcesManager::ResourceType> nauticalTypes;
     nauticalTypes << OsmAnd::ResourcesManager::ResourceType::DepthMapRegion;
     NSArray<NSString *> *nauticalFiles = [OAResourcesUIHelper getInstalledResourcePathsByTypes:nauticalTypes includeHidden:NO];
@@ -526,7 +615,11 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         }];
         resourcesItems[OAExportSettingsType.DEPTH_DATA] = sortedFiles;
     }
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG resources nautical duration=%.3f ms count=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 nauticalFiles.count]];
 
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
     QSet<OsmAnd::ResourcesManager::ResourceType> terrainTypes;
     terrainTypes << OsmAnd::ResourcesManager::ResourceType::SrtmMapRegion;
     terrainTypes << OsmAnd::ResourcesManager::ResourceType::HillshadeRegion;
@@ -540,6 +633,9 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
         }];
         resourcesItems[OAExportSettingsType.TERRAIN_DATA] = sortedFiles;
     }
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG resources terrain duration=%.3f ms count=%ld",
+                                 (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                 terrainFiles.count]];
     
 //    files = getFilesByType(localIndexInfoList, LocalIndexType.TTS_VOICE_DATA);
 //    if (!files.isEmpty()) {
@@ -550,6 +646,8 @@ - (void) exportSettings:(NSString *)fileDir fileName:(NSString *)fileName settin
 //        resourcesItems.put(ExportSettingsType.VOICE, files);
 //    }
     
+    [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG resources TOTAL duration=%.3f ms",
+                                 (CFAbsoluteTimeGetCurrent() - methodStartTime) * 1000]];
     return resourcesItems;
 }
 
diff --git a/Sources/Backup/OABackupDbHelper.m b/Sources/Backup/OABackupDbHelper.m
index 4e2f601dd0..1717058006 100644
--- a/Sources/Backup/OABackupDbHelper.m
+++ b/Sources/Backup/OABackupDbHelper.m
@@ -7,6 +7,8 @@
 //
 
 #import "OABackupDbHelper.h"
+#import "OABackupHelper.h"
+#import "OAOperationLog.h"
 
 #import <sqlite3.h>
 
@@ -105,6 +107,9 @@ @implementation OABackupDbHelper
     
     sqlite3 *backupFilesDB;
     dispatch_queue_t dbQueue;
+
+    // COLLECT_LOCAL_DIAG: remove after cloud sync performance investigation.
+    OAOperationLog *_cloudSyncOperationLog;
 }
 
 + (OABackupDbHelper *)sharedDatabase
@@ -130,6 +135,7 @@ - (instancetype)init
             [[NSFileManager defaultManager] createDirectoryAtPath:dir withIntermediateDirectories:YES attributes:nil error:nil];
         
         dbQueue = dispatch_queue_create("backup_dbQueue", DISPATCH_QUEUE_SERIAL);
+        _cloudSyncOperationLog = [[OAOperationLog alloc] initWithOperationName:@"cloudSyncDatabase" debug:BACKUP_DEBUG_LOGS];
         
         [self load];
     }
@@ -300,15 +306,22 @@ - (void) addUploadedFileInfo:(OAUploadedFileInfo *)info
 
 - (NSDictionary<NSString *, OAUploadedFileInfo *> *) getUploadedFileInfoMap
 {
+    [_cloudSyncOperationLog startOperation:@"COLLECT_LOCAL_DIAG getUploadedFileInfoMap"];
+    CFAbsoluteTime methodStartTime = CFAbsoluteTimeGetCurrent();
     NSMutableDictionary<NSString *, OAUploadedFileInfo *> *res = [NSMutableDictionary dictionary];
     
     dispatch_sync(dbQueue, ^{
-        
+        CFAbsoluteTime queueStartTime = CFAbsoluteTimeGetCurrent();
+        [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG dbQueue entered wait=%.3f ms",
+                                     (queueStartTime - methodStartTime) * 1000]];
+
         const char *dbpath = [_dbFilePath UTF8String];
         sqlite3_stmt *statement;
-        
+        CFAbsoluteTime phaseStartTime = CFAbsoluteTimeGetCurrent();
         if (sqlite3_open(dbpath, &backupFilesDB) == SQLITE_OK)
         {
+            [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG sqlite_open END duration=%.3f ms success=1",
+                                         (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000]];
             NSString *querySQL = [NSString stringWithFormat:@"SELECT %@, %@, %@, %@ FROM %@",
                                   UPLOADED_FILE_COL_TYPE,
                                   UPLOADED_FILE_COL_NAME,
@@ -316,8 +329,13 @@ - (void) addUploadedFileInfo:(OAUploadedFileInfo *)info
                                   UPLOADED_FILE_COL_MD5_DIGEST,
                                   UPLOADED_FILES_TABLE_NAME];
             const char *query_stmt = [querySQL UTF8String];
+            phaseStartTime = CFAbsoluteTimeGetCurrent();
             if (sqlite3_prepare_v2(backupFilesDB, query_stmt, -1, &statement, NULL) == SQLITE_OK)
             {
+                [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG sqlite_prepare END duration=%.3f ms success=1",
+                                             (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000]];
+                phaseStartTime = CFAbsoluteTimeGetCurrent();
+                NSInteger rowCount = 0;
                 while (sqlite3_step(statement) == SQLITE_ROW)
                 {
                     NSString *type = [[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(statement, 0)];
@@ -326,12 +344,32 @@ - (void) addUploadedFileInfo:(OAUploadedFileInfo *)info
                     NSString *md5Digest = [[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(statement, 3)];
                     OAUploadedFileInfo *info = [[OAUploadedFileInfo alloc] initWithType:type name:name uploadTime:uploadTime md5Digest:md5Digest];
                     res[[NSString stringWithFormat:@"%@___%@", info.type, info.name]] = info;
+                    rowCount++;
                 }
+                [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG sqlite_rows END duration=%.3f ms rows=%ld",
+                                             (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                             rowCount]];
                 sqlite3_finalize(statement);
             }
+            else
+            {
+                [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG sqlite_prepare END duration=%.3f ms success=0 code=%d",
+                                             (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                             sqlite3_errcode(backupFilesDB)]];
+            }
+            phaseStartTime = CFAbsoluteTimeGetCurrent();
             sqlite3_close(backupFilesDB);
+            [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG sqlite_close END duration=%.3f ms",
+                                         (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000]];
+        }
+        else
+        {
+            [_cloudSyncOperationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG sqlite_open END duration=%.3f ms success=0 code=%d",
+                                         (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                                         sqlite3_errcode(backupFilesDB)]];
         }
     });
+    [_cloudSyncOperationLog finishOperation:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG count=%ld", res.count]];
     return res;
 }
 
diff --git a/Sources/Backup/OACollectLocalFilesTask.m b/Sources/Backup/OACollectLocalFilesTask.m
index 2ac3a86ec5..786ee55612 100644
--- a/Sources/Backup/OACollectLocalFilesTask.m
+++ b/Sources/Backup/OACollectLocalFilesTask.m
@@ -44,10 +44,24 @@ - (instancetype) initWithListener:(id<OAOnCollectLocalFilesListener>)listener
 
 - (void) execute
 {
+    CFAbsoluteTime executeStartTime = CFAbsoluteTimeGetCurrent();
+    [_operationLog log:@"COLLECT_LOCAL_DIAG execute BEGIN"];
     dispatch_async(dispatch_get_global_queue(QOS_CLASS_USER_INITIATED, 0), ^{
-        
+        [_operationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG worker BEGIN queueWait=%.3f ms",
+                            (CFAbsoluteTimeGetCurrent() - executeStartTime) * 1000]];
+
         NSMutableArray<OALocalFile *> *result = [NSMutableArray array];
+        CFAbsoluteTime phaseStartTime = CFAbsoluteTimeGetCurrent();
+        [_operationLog log:@"COLLECT_LOCAL_DIAG getUploadedFileInfoMap BEGIN"];
         _infos = [_dbHelper getUploadedFileInfoMap];
+
+        [_operationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG getUploadedFileInfoMap END duration=%.3f ms count=%ld",
+                            (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                            _infos.count]];
+
+        phaseStartTime = CFAbsoluteTimeGetCurrent();
+        [_operationLog log:@"COLLECT_LOCAL_DIAG getLocalItems BEGIN"];
+
         NSMutableDictionary<NSString *, OAUploadedFileInfo *> *normalized = [NSMutableDictionary dictionaryWithCapacity:_infos.count];
         [_infos enumerateKeysAndObjectsUsingBlock:^(NSString *key, OAUploadedFileInfo *info, BOOL *stop) {
             NSString *decomposedKey = key.decomposedStringWithCanonicalMapping;
@@ -56,9 +70,15 @@ - (void) execute
                 normalized[decomposedKey] = info;
         }];
         _infos = normalized;
+
         NSArray<OASettingsItem *> *localItems = [self getLocalItems];
+        [_operationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG getLocalItems END duration=%.3f ms count=%ld",
+                            (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                            localItems.count]];
         NSFileManager *fileManager = NSFileManager.defaultManager;
         [_operationLog log:@"getLocalItems"];
+        phaseStartTime = CFAbsoluteTimeGetCurrent();
+        [_operationLog log:@"COLLECT_LOCAL_DIAG createLocalFiles loop BEGIN"];
         for (OASettingsItem *item in localItems)
         {
             NSString *fileName = [BackupUtils getItemFileName:item];
@@ -158,6 +178,9 @@ - (void) execute
                          lastModified:item.lastModifiedTime];
             }
         }
+        [_operationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG createLocalFiles loop END duration=%.3f ms files=%ld",
+                            (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                            result.count]];
         dispatch_async(dispatch_get_main_queue(), ^{
             [_operationLog finishOperation:[NSString stringWithFormat:@"Files=%ld", result.count]];
             if (_listener)
@@ -193,7 +216,15 @@ - (void) createLocalFile:(NSMutableArray<OALocalFile *> *)result item:(OASetting
                 && lastMd5.length > 0;
             if (needM5Digest && filePath && [NSFileManager.defaultManager fileExistsAtPath:filePath])
             {
+                CFAbsoluteTime md5StartTime = CFAbsoluteTimeGetCurrent();
                 NSString *md5 = [OAUtilities fileMD5:filePath];
+                CFAbsoluteTime md5DurationMs = (CFAbsoluteTimeGetCurrent() - md5StartTime) * 1000;
+                if (md5DurationMs >= 50)
+                {
+                    [_operationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG slow fileMD5 duration=%.3f ms file=%@",
+                                        md5DurationMs,
+                                        fileName]];
+                }
                 if ([md5 isEqualToString:lastMd5])
                 {
                     item.localModifiedTime = localFile.uploadTime;
@@ -208,8 +239,18 @@ - (void) createLocalFile:(NSMutableArray<OALocalFile *> *)result item:(OASetting
 
 - (NSArray<OASettingsItem *> *) getLocalItems
 {
+    CFAbsoluteTime phaseStartTime = CFAbsoluteTimeGetCurrent();
     NSArray<OAExportSettingsType *> *types = [self getEnabledExportTypes];
-    return [OASettingsHelper.sharedInstance getFilteredSettingsItems:types addProfiles:YES doExport:YES];
+    [_operationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG getEnabledExportTypes END duration=%.3f ms count=%ld",
+                        (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                        types.count]];
+
+    phaseStartTime = CFAbsoluteTimeGetCurrent();
+    NSArray<OASettingsItem *> *items = [OASettingsHelper.sharedInstance getFilteredSettingsItems:types addProfiles:YES doExport:YES];
+    [_operationLog log:[NSString stringWithFormat:@"COLLECT_LOCAL_DIAG getFilteredSettingsItems END duration=%.3f ms count=%ld",
+                        (CFAbsoluteTimeGetCurrent() - phaseStartTime) * 1000,
+                        items.count]];
+    return items;
 }
 
 - (NSArray<OAExportSettingsType *> *)getEnabledExportTypes