all: Transition to using fs watcher by default (fixes #4552)

etc/linux-systemd/system/syncthing@.service

@@ -2,7 +2,6 @@
 Description=Syncthing - Open Source Continuous File Synchronization for %I
 Documentation=man:syncthing(1)
 After=network.target
-Wants=syncthing-inotify@.service
 
 [Service]
 User=%i

etc/linux-systemd/user/syncthing.service

@@ -1,7 +1,6 @@
 [Unit]
 Description=Syncthing - Open Source Continuous File Synchronization
 Documentation=man:syncthing(1)
-Wants=syncthing-inotify.service
 
 [Service]
 ExecStart=/usr/bin/syncthing -no-browser -no-restart -logflags=0

gui/default/assets/lang/lang-en.json

@@ -12,6 +12,7 @@
    "Add Remote Device": "Add Remote Device",
    "Add devices from the introducer to our device list, for mutually shared folders.": "Add devices from the introducer to our device list, for mutually shared folders.",
    "Add new folder?": "Add new folder?",
+   "Additionally the full rescan interval will be increased (times 60, i.e. new default of 1h). You can also configure it manually for every folder later after choosing No.": "Additionally the full rescan interval will be increased (times 60, i.e. new default of 1h). You can also configure it manually for every folder later after choosing No.",
    "Address": "Address",
    "Addresses": "Addresses",
    "Advanced": "Advanced",
@@ -49,6 +50,7 @@
    "Connection Error": "Connection Error",
    "Connection Type": "Connection Type",
    "Connections": "Connections",
+   "Continuously watching for changes is now available within Syncthing. This will detect changes on disk and issue a scan on only the modified paths. The benefits are that changes are propagated quicker and that less full scans are required.": "Continuously watching for changes is now available within Syncthing. This will detect changes on disk and issue a scan on only the modified paths. The benefits are that changes are propagated quicker and that less full scans are required.",
    "Copied from elsewhere": "Copied from elsewhere",
    "Copied from original": "Copied from original",
    "Copyright © 2014-2016 the following Contributors:": "Copyright © 2014-2016 the following Contributors:",
@@ -75,6 +77,7 @@
    "Discovery Failures": "Discovery Failures",
    "Do not restore": "Do not restore",
    "Do not restore all": "Do not restore all",
+   "Do you want to enable watching for changes for all your folders?": "Do you want to enable watching for changes for all your folders?",
    "Documentation": "Documentation",
    "Download Rate": "Download Rate",
    "Downloaded": "Downloaded",
@@ -114,6 +117,7 @@
    "Folder Path": "Folder Path",
    "Folder Type": "Folder Type",
    "Folders": "Folders",
+   "Full Rescan Interval (s)": "Full Rescan Interval (s)",
    "GUI": "GUI",
    "GUI Authentication Password": "GUI Authentication Password",
    "GUI Authentication User": "GUI Authentication User",
@@ -193,6 +197,7 @@
    "Periodic scanning at given interval and disabled watching for changes": "Periodic scanning at given interval and disabled watching for changes",
    "Periodic scanning at given interval and enabled watching for changes": "Periodic scanning at given interval and enabled watching for changes",
    "Periodic scanning at given interval and failed setting up watching for changes, retrying every 1m:": "Periodic scanning at given interval and failed setting up watching for changes, retrying every 1m:",
+   "Permissions": "Permissions",
    "Please consult the release notes before performing a major upgrade.": "Please consult the release notes before performing a major upgrade.",
    "Please set a GUI Authentication User and Password in the Settings dialog.": "Please set a GUI Authentication User and Password in the Settings dialog.",
    "Please wait": "Please wait",
@@ -328,6 +333,9 @@
    "Warning, this path is a parent directory of an existing folder \"{%otherFolderLabel%}\" ({%otherFolder%}).": "Warning, this path is a parent directory of an existing folder \"{{otherFolderLabel}}\" ({{otherFolder}}).",
    "Warning, this path is a subdirectory of an existing folder \"{%otherFolder%}\".": "Warning, this path is a subdirectory of an existing folder \"{{otherFolder}}\".",
    "Warning, this path is a subdirectory of an existing folder \"{%otherFolderLabel%}\" ({%otherFolder%}).": "Warning, this path is a subdirectory of an existing folder \"{{otherFolderLabel}}\" ({{otherFolder}}).",
+   "Warning: If you are using an external watcher like {%syncthingInotify%}, you should make sure it is deactivated.": "Warning: If you are using an external watcher like {{syncthingInotify}}, you should make sure it is deactivated.",
+   "Watch for Changes": "Watch for Changes",
+   "Watching for Changes": "Watching for Changes",
    "When adding a new device, keep in mind that this device must be added on the other side too.": "When adding a new device, keep in mind that this device must be added on the other side too.",
    "When adding a new folder, keep in mind that the Folder ID is used to tie folders together between devices. They are case sensitive and must match exactly between all devices.": "When adding a new folder, keep in mind that the Folder ID is used to tie folders together between devices. They are case sensitive and must match exactly between all devices.",
    "Yes": "Yes",

gui/default/syncthing/core/notifications.html

@@ -41,3 +41,31 @@
     </div>
   </div>
 </notification>
+
+<notification id="fsWatcherNotification">
+  <div class="panel panel-success">
+    <div class="panel-heading">
+      <h3 class="panel-title"><span class="fa fa-flash"></span>&ensp;<span translate>Watching for Changes</span></h3>
+    </div>
+    <div class="panel-body">
+      <p translate>Continuously watching for changes is now available within Syncthing. This will detect changes on disk and issue a scan on only the modified paths. The benefits are that changes are propagated quicker and that less full scans are required.</p>
+      <p><a href="https://docs.syncthing.net/users/syncing.html#scanning"><span class="fa fa-fw fa-book"></span>&nbsp;<span translate>Learn more</span></a></p>
+      <p>
+        <span translate>Do you want to enable watching for changes for all your folders?</span><br/>
+        <span translate>Additionally the full rescan interval will be increased (times 60, i.e. new default of 1h). You can also configure it manually for every folder later after choosing No.</span>
+      </p>
+      <p translate translate-value-syncthing-inotify="syncthing-inotify">Warning: If you are using an external watcher like {%syncthingInotify%}, you should make sure it is deactivated.</p>
+    </div>
+    <div class="panel-footer clearfix">
+      <div class="pull-right">
+        <button type="button" class="btn btn-primary btn-sm" ng-click="activateAllFsWatchers(); dismiss()">
+          <span class="fa fa-check"></span>&nbsp;<span translate>Yes</span>
+        </button>
+        <button type="button" class="btn btn-default btn-sm" ng-click="dismiss()">
+          <span class="fa fa-times"></span>&nbsp;<span translate>No</span>
+        </button>
+      </div>
+      <div class="clearfix"></div>
+    </div>
+  </div>
+</notification>

gui/default/syncthing/core/syncthingController.js

@@ -53,6 +53,7 @@ angular.module('syncthing.core')
         $scope.globalChangeEvents = {};
         $scope.metricRates = false;
         $scope.folderPathErrors = {};
+        $scope.currentFolder = {};
         resetRemoteNeed();
 
         try {
@@ -62,8 +63,9 @@ angular.module('syncthing.core')
         $scope.folderDefaults = {
             selectedDevices: {},
             type: "readwrite",
-            rescanIntervalS: 60,
+            rescanIntervalS: 3600,
             fsWatcherDelayS: 10,
+            fsWatcherEnabled: true,
             minDiskFree: {value: 1, unit: "%"},
             maxConflicts: 10,
             fsync: true,
@@ -1504,6 +1506,14 @@ angular.module('syncthing.core')
             $scope.currentFolder.path = pathJoin($scope.config.options.defaultFolderPath, newvalue);
         });
 
+        $scope.$watch('currentFolder.fsWatcherEnabled', function (newvalue) {
+            if (newvalue) {
+                $scope.currentFolder.rescanIntervalS = 3600;
+            } else {
+                $scope.currentFolder.rescanIntervalS = 60;
+            }
+        });
+
         $scope.loadFormIntoScope = function (form) {
             console.log('loadFormIntoScope',form.$name);
             switch (form.$name) {
@@ -2126,6 +2136,28 @@ angular.module('syncthing.core')
             return false;
         };
 
+        $scope.activateAllFsWatchers = function() {
+            var folders = $scope.folderList();
+
+            $.each(folders, function(i) {
+                if (folders[i].fsWatcherEnabled) {
+                    return;
+                }
+                folders[i].fsWatcherEnabled = true;
+                if (folders[i].rescanIntervalS === 0) {
+                    return;
+                }
+                // Delay full scans, but scan at least once per day
+                folders[i].rescanIntervalS *= 60;
+                if (folders[i].rescanIntervalS > 86400) {
+                    folders[i].rescanIntervalS = 86400;
+                }
+            });
+
+            $scope.config.folders = folders;
+            $scope.saveConfig();
+        };
+
         $scope.bumpFile = function (folder, file) {
             var url = urlbase + "/db/prio?folder=" + encodeURIComponent(folder) + "&file=" + encodeURIComponent(file);
             // In order to get the right view of data in the response.

gui/default/syncthing/folder/editFolderModalView.html

@@ -133,26 +133,75 @@
           <div class="pull-left" ng-show="!editingExisting"><span translate translate-value-path="{{currentFolder.path}}{{system.pathSeparator}}.stignore">Creating ignore patterns, overwriting an existing file at {%path%}.</span></div>
         </div>
         <div id="folder-advanced" class="tab-pane">
-          <div class="row">
+          <div class="row form-group" ng-class="{'has-error': folderEditor.rescanIntervalS.$invalid && folderEditor.rescanIntervalS.$dirty}">
-            <div class="col-md-6">
+            <div class="col-md-12">
-              <div class="form-group" ng-class="{'has-error': folderEditor.rescanIntervalS.$invalid && folderEditor.rescanIntervalS.$dirty}">
+              <label translate>Scanning</label>
-                <label for="rescanIntervalS"><span translate>Rescan Interval</span> (s)</label><br/>
+              &nbsp;<a href="https://docs.syncthing.net/users/syncing.html#scanning" target="_blank"><span class="fa fa-book"></span>&nbsp;<span translate>Help</span></a></br>
-                <input name="rescanIntervalS" id="rescanIntervalS" class="form-control" type="number" ng-model="currentFolder.rescanIntervalS" required=""  aria-required="true" min="0"/>
+              <div class="row">
-                <p class="help-block">
+                <div class="col-md-6">
-                  <span translate ng-if="!folderEditor.rescanIntervalS.$valid && folderEditor.rescanIntervalS.$dirty">The rescan interval must be a non-negative number of seconds.</span>
+                  <input type="checkbox" ng-model="currentFolder.fsWatcherEnabled" tooltip data-original-title="{{'Use notifications from the filesystem to detect changed items.' | translate }}">&nbsp;<span translate>Watch for Changes</span>
-                </p>
+                </div>
+                <div class="col-md-6">
+                  <div class="row">
+                    <span class="col-md-8" translate>Full Rescan Interval (s)</span>
+                    <div class="col-md-4">
+                      <input name="rescanIntervalS" id="rescanIntervalS" class="form-control"  type="number" ng-model="currentFolder.rescanIntervalS" required="" aria-required="true" min="0"/>
+                    </div>
+                  </div>
+                  <p class="help-block" ng-if="!folderEditor.rescanIntervalS.$valid && folderEditor.rescanIntervalS.$dirty" translate>
+                    The rescan interval must be a non-negative number of seconds.
+                  </p>
+                </div>
               </div>
             </div>
-            <div class="col-md-6 form-horizontal">
+          </div>
-              <div class="form-group" ng-class="{'has-error': folderEditor.minDiskFree.$invalid && folderEditor.minDiskFree.$dirty}">
+          <div class="row">
-                <label class="col-xs-12" for="minDiskFree"><span translate>Minimum Free Disk Space</span></label><br/>
+            <div class="col-md-6 form-group">
-                <div class="col-xs-9"><input name="minDiskFree" id="minDiskFree" class="form-control" type="number" ng-model="currentFolder.minDiskFree.value" required=""  aria-required="true" min="0" step="0.01"/></div>
+              <label translate>Folder Type</label>
-                <div class="col-xs-3"><select class="col-sm-3 form-control" ng-model="currentFolder.minDiskFree.unit">
+              &nbsp;<a href="https://docs.syncthing.net/users/foldertypes.html" target="_blank"><span class="fa fa-book"></span>&nbsp;<span translate>Help</span></a>
+              <select class="form-control" ng-model="currentFolder.type">
+                <option value="readwrite" translate>Send &amp; Receive</option>
+                <option value="readonly" translate>Send Only</option>
+              </select>
+              <p ng-if="currentFolder.type == 'readonly'" translate class="help-block">Files are protected from changes made on other devices, but changes made on this device will be sent to the rest of the cluster.</p>
+            </div>
+            <div class="col-md-6 form-group">
+              <label translate>File Pull Order</label>
+              <select class="form-control" ng-model="currentFolder.order">
+                <option value="random" translate>Random</option>
+                <option value="alphabetic" translate>Alphabetic</option>
+                <option value="smallestFirst" translate>Smallest First</option>
+                <option value="largestFirst" translate>Largest First</option>
+                <option value="oldestFirst" translate>Oldest First</option>
+                <option value="newestFirst" translate>Newest First</option>
+              </select>
+            </div>
+          </div>
+          <div class="row">
+            <div class="col-md-6 form-horizontal form-group" ng-class="{'has-error': folderEditor.minDiskFree.$invalid && folderEditor.minDiskFree.$dirty}">
+              <label for="minDiskFree" translate>Minimum Free Disk Space</label><br/>
+              <div class="row">
+                <div class="col-md-9">
+                  <input name="minDiskFree" id="minDiskFree" class="form-control" type="number" ng-model="currentFolder.minDiskFree.value" required=""  aria-required="true" min="0" step="0.01"/>
+                </div>
+                <div class="col-md-3">
+                  <select class="form-control" ng-model="currentFolder.minDiskFree.unit">
                     <option value="%">%</option>
                     <option value="kB">kB</option>
                     <option value="MB">MB</option>
                     <option value="GB">GB</option>
                     <option value="TB">TB</option>
+                  </select>
+                </div>
+              </div>
+              <p class="help-block" ng-show="folderEditor.minDiskFree.$invalid" translate>
+                Enter a non-negative number (e.g., "2.35") and select a unit. Percentages are as part of the total disk size.
+              </p>
+            </div>
+            <div class="col-md-6 form-group">
+              <label translate>Permissions</label><br/>
+              <input type="checkbox" ng-model="currentFolder.ignorePerms"/> <span translate>Ignore</span>
+              <p translate class="help-block">File permission bits are ignored when looking for changes. Use on FAT file systems.</p>
                 </select></div>
                 <p class="col-xs-12 help-block" ng-show="folderEditor.minDiskFree.$invalid">
                   <span translate>Enter a non-negative number (e.g., "2.35") and select a unit. Percentages are as part of the total disk size.</span>
@@ -160,43 +209,6 @@
               </div>
             </div>
           </div>
-          <div class="row">
-            <!-- Left column -->
-            <div class="col-md-6">
-              <div class="form-group">
-                <label translate>Folder Type</label>
-                &nbsp;<a href="https://docs.syncthing.net/users/foldertypes.html" target="_blank"><span class="fa fa-book"></span>&nbsp;<span translate>Help</span></a>
-                <select class="form-control" ng-model="currentFolder.type">
-                  <option value="readwrite" translate>Send &amp; Receive</option>
-                  <option value="readonly" translate>Send Only</option>
-                </select>
-                <p ng-if="currentFolder.type == 'readonly'" translate class="help-block">Files are protected from changes made on other devices, but changes made on this device will be sent to the rest of the cluster.</p>
-              </div>
-              <div class="form-group">
-                <div class="checkbox">
-                  <label>
-                    <input type="checkbox" ng-model="currentFolder.ignorePerms"/> <span translate>Ignore Permissions</span>
-                  </label>
-                </div>
-                <p translate class="help-block">File permission bits are ignored when looking for changes. Use on FAT file systems.</p>
-              </div>
-            </div>
-
-            <!-- Right column-->
-            <div class="col-md-6">
-              <div class="form-group">
-                <label translate>File Pull Order</label>
-                <select class="form-control" ng-model="currentFolder.order">
-                  <option value="random" translate>Random</option>
-                  <option value="alphabetic" translate>Alphabetic</option>
-                  <option value="smallestFirst" translate>Smallest First</option>
-                  <option value="largestFirst" translate>Largest First</option>
-                  <option value="oldestFirst" translate>Oldest First</option>
-                  <option value="newestFirst" translate>Newest First</option>
-                </select>
-              </div>
-            </div>
-          </div>
         </div>
       </div>
     </form>

lib/config/config.go

@@ -32,7 +32,7 @@ import (
 
 const (
 	OldestHandledVersion = 10
-	CurrentVersion       = 27
+	CurrentVersion       = 28
 	MaxRescanIntervalS   = 365 * 24 * 60 * 60
 )
 
@@ -315,6 +315,9 @@ func (cfg *Configuration) clean() error {
 	if cfg.Version == 26 {
 		convertV26V27(cfg)
 	}
+	if cfg.Version == 27 {
+		convertV27V28(cfg)
+	}
 
 	// Build a list of available devices
 	existingDevices := make(map[protocol.DeviceID]bool)
@@ -374,6 +377,12 @@ func (cfg *Configuration) clean() error {
 	return nil
 }
 
+func convertV27V28(cfg *Configuration) {
+	// Show a notification about enabling filesystem watching
+	cfg.Options.UnackedNotificationIDs = append(cfg.Options.UnackedNotificationIDs, "fsWatcherNotification")
+	cfg.Version = 28
+}
+
 func convertV26V27(cfg *Configuration) {
 	for i := range cfg.Folders {
 		f := &cfg.Folders[i]

lib/config/config_test.go

@@ -206,7 +206,8 @@ func TestOverriddenValues(t *testing.T) {
 		OverwriteRemoteDevNames: true,
 		TempIndexMinBlocks:      100,
 		UnackedNotificationIDs: []string{
-			"channelNotification", // added in 17->18 migration
+			"channelNotification",   // added in 17->18 migration
+			"fsWatcherNotification", // added in 27->28 migration
 		},
 		WeakHashSelectionMethod: WeakHashNever,
 		DefaultFolderPath:       "/media/syncthing",

lib/config/folderconfiguration.go

@@ -67,16 +67,17 @@ type FolderDeviceConfiguration struct {
 
 func NewFolderConfiguration(myID protocol.DeviceID, id, label string, fsType fs.FilesystemType, path string) FolderConfiguration {
 	f := FolderConfiguration{
-		ID:              id,
+		ID:               id,
-		Label:           label,
+		Label:            label,
-		RescanIntervalS: 60,
+		RescanIntervalS:  3600,
-		FSWatcherDelayS: 10,
+		FSWatcherEnabled: true,
-		MinDiskFree:     Size{Value: 1, Unit: "%"},
+		FSWatcherDelayS:  10,
-		Devices:         []FolderDeviceConfiguration{{DeviceID: myID}},
+		MinDiskFree:      Size{Value: 1, Unit: "%"},
-		AutoNormalize:   true,
+		Devices:          []FolderDeviceConfiguration{{DeviceID: myID}},
-		MaxConflicts:    -1,
+		AutoNormalize:    true,
-		FilesystemType:  fsType,
+		MaxConflicts:     -1,
-		Path:            path,
+		FilesystemType:   fsType,
+		Path:             path,
 	}
 	f.prepare()
 	return f

lib/config/testdata/v25.xml

@@ -1,5 +1,5 @@
 <configuration version="25">
-    <folder id="test" path="testdata" type="readonly" ignorePerms="false" rescanIntervalS="600" fsNotifications="false" notifyDelayS="10" autoNormalize="true">
+    <folder id="test" path="testdata" type="readonly" ignorePerms="false" rescanIntervalS="600" fsWatcherEnabled="false" fsWatcherDelayS="10" autoNormalize="true">
         <filesystemType>basic</filesystemType>
         <device id="AIR6LPZ-7K4PTTV-UXQSMUU-CPQ5YWH-OEDFIIQ-JUG777G-2YQXXR5-YD6AWQR"></device>
         <device id="P56IOI7-MZJNU2Y-IQGDREY-DM2MGTI-MGL3BXN-PQ6W5BM-TBBZ4TJ-XZWICQ2"></device>

lib/config/testdata/v26.xml

@@ -1,5 +1,5 @@
 <configuration version="26">
-    <folder id="test" path="testdata" type="readonly" ignorePerms="false" rescanIntervalS="600" fsNotifications="false" notifyDelayS="10" autoNormalize="true">
+    <folder id="test" path="testdata" type="readonly" ignorePerms="false" rescanIntervalS="600" fsWatcherEnabled="false" fsWatcherDelayS="10" autoNormalize="true">
         <filesystemType>basic</filesystemType>
         <device id="AIR6LPZ-7K4PTTV-UXQSMUU-CPQ5YWH-OEDFIIQ-JUG777G-2YQXXR5-YD6AWQR"></device>
         <device id="P56IOI7-MZJNU2Y-IQGDREY-DM2MGTI-MGL3BXN-PQ6W5BM-TBBZ4TJ-XZWICQ2"></device>

lib/config/testdata/v27.xml

@@ -1,5 +1,5 @@
 <configuration version="27">
-    <folder id="test" path="testdata" type="readonly" ignorePerms="false" rescanIntervalS="600" fsNotifications="false" notifyDelayS="10" autoNormalize="true">
+    <folder id="test" path="testdata" type="readonly" ignorePerms="false" rescanIntervalS="600" fsWatcherEnabled="false" fsWatcherDelayS="10" autoNormalize="true">
         <filesystemType>basic</filesystemType>
         <device id="AIR6LPZ-7K4PTTV-UXQSMUU-CPQ5YWH-OEDFIIQ-JUG777G-2YQXXR5-YD6AWQR"></device>
         <device id="P56IOI7-MZJNU2Y-IQGDREY-DM2MGTI-MGL3BXN-PQ6W5BM-TBBZ4TJ-XZWICQ2"></device>

lib/config/testdata/v28.xml

@@ -0,0 +1,16 @@
+<configuration version="28">
+    <folder id="test" path="testdata" type="readonly" ignorePerms="false" rescanIntervalS="600" fsWatcherEnabled="false" fsWatcherDelayS="10" autoNormalize="true">
+        <filesystemType>basic</filesystemType>
+        <device id="AIR6LPZ-7K4PTTV-UXQSMUU-CPQ5YWH-OEDFIIQ-JUG777G-2YQXXR5-YD6AWQR"></device>
+        <device id="P56IOI7-MZJNU2Y-IQGDREY-DM2MGTI-MGL3BXN-PQ6W5BM-TBBZ4TJ-XZWICQ2"></device>
+        <minDiskFree unit="%">1</minDiskFree>
+        <maxConflicts>-1</maxConflicts>
+        <fsync>true</fsync>
+    </folder>
+    <device id="AIR6LPZ-7K4PTTV-UXQSMUU-CPQ5YWH-OEDFIIQ-JUG777G-2YQXXR5-YD6AWQR" name="node one" compression="metadata">
+        <address>tcp://a</address>
+    </device>
+    <device id="P56IOI7-MZJNU2Y-IQGDREY-DM2MGTI-MGL3BXN-PQ6W5BM-TBBZ4TJ-XZWICQ2" name="node two" compression="metadata">
+        <address>tcp://b</address>
+    </device>
+</configuration>