diff --git a/Common/sources/operationContext.js b/Common/sources/operationContext.js
index 75d276e7..a87d56ad 100644
--- a/Common/sources/operationContext.js
+++ b/Common/sources/operationContext.js
@@ -53,6 +53,8 @@ Context.prototype.init = function(tenant, docId, userId, opt_shardKey, opt_WopiS
   this.config = null;
   this.secret = null;
   this.license = null;
+  //cache
+  this.taskResultCache = null;
 };
 Context.prototype.initDefault = function() {
   this.init(tenantManager.getDefautTenant(), constants.DEFAULT_DOC_ID, constants.DEFAULT_USER_ID, undefined);
diff --git a/DocService/sources/DocsCoServer.js b/DocService/sources/DocsCoServer.js
index 081b42fc..0987dc20 100644
--- a/DocService/sources/DocsCoServer.js
+++ b/DocService/sources/DocsCoServer.js
@@ -962,9 +962,21 @@ async function applyForceSaveCache(ctx, docId, forceSave, type, opt_userConnecti
       res.notModified = true;
     }
   } else if (!forceSave.started) {
-      res.startedForceSave = await editorData.checkAndStartForceSave(ctx, docId);
-      res.ok = !!res.startedForceSave;
-      return res;
+    const isTypeToSendFile = commonDefines.c_oAscForceSaveTypes.Command === type ||
+      commonDefines.c_oAscForceSaveTypes.Button === type ||
+      commonDefines.c_oAscForceSaveTypes.Timeout === type ||
+      commonDefines.c_oAscForceSaveTypes.Form === type;
+    if (isTypeToSendFile) {
+      const selectRes = await taskResult.selectWithCache(ctx, docId);
+      if (selectRes.length > 0 && !selectRes[0].callback) {
+        ctx.logger.debug('applyForceSaveCache empty callback: %s', docId);
+        res.notModified = true;
+        return res;
+      }
+    }
+    res.startedForceSave = await editorData.checkAndStartForceSave(ctx, docId);
+    res.ok = !!res.startedForceSave;
+    return res;
   } else if (commonDefines.c_oAscForceSaveTypes.Form === type || commonDefines.c_oAscForceSaveTypes.Internal === type) {
     res.ok = true;
     res.inProgress = true;
@@ -1407,13 +1419,13 @@ function* cleanDocumentOnExit(ctx, docId, deleteChanges, opt_userIndex) {
   }
   yield unlockWopiDoc(ctx, docId, opt_userIndex);
 }
-function* cleanDocumentOnExitNoChanges(ctx, docId, opt_userId, opt_userIndex, opt_forceClose) {
+function* cleanDocumentOnExitNoChanges(ctx, docId, opt_userId, opt_userIndex, opt_forceClose, opt_deleteChanges) {
   var userAction = opt_userId ? new commonDefines.OutputAction(commonDefines.c_oAscUserAction.Out, opt_userId) : null;
   // We send that everyone is gone and there are no changes (to set the status on the server about the end of editing)
   yield sendStatusDocument(ctx, docId, c_oAscChangeBase.No, userAction, opt_userIndex, undefined, undefined, undefined, opt_forceClose);
   //if the user entered the document, the connection was broken, all information was deleted on the server,
   //when the connection is restored, the userIndex will be saved and it will match the userIndex of the next user
-  yield* cleanDocumentOnExit(ctx, docId, false, opt_userIndex);
+  yield* cleanDocumentOnExit(ctx, docId, opt_deleteChanges || false, opt_userIndex);
 }
 
 function createSaveTimer(ctx, docId, opt_userId, opt_userIndex, opt_userLcid, opt_queue, opt_noDelay, opt_initShardKey) {
diff --git a/DocService/sources/ai/aiProxyHandler.js b/DocService/sources/ai/aiProxyHandler.js
index 001ae83e..c7ba16b3 100644
--- a/DocService/sources/ai/aiProxyHandler.js
+++ b/DocService/sources/ai/aiProxyHandler.js
@@ -39,6 +39,7 @@ const utils = require('./../../../Common/sources/utils');
 const operationContext = require('./../../../Common/sources/operationContext');
 const commonDefines = require('./../../../Common/sources/commondefines');
 const docsCoServer = require('./../DocsCoServer');
+const statsDClient = require('./../../../Common/sources/statsdclient');
 
 // Import the new aiEngine module
 const aiEngine = require('./aiEngineWrapper');
@@ -49,6 +50,7 @@ const cfgTokenEnableBrowser = config.get('services.CoAuthoring.token.enable.brow
 const cfgAiSettings = config.get('aiSettings');
 
 const AI = aiEngine.AI;
+const clientStatsD = statsDClient.getClient();
 /**
  * Helper function to set CORS headers if the request origin is allowed
  * 
@@ -149,6 +151,8 @@ async function proxyRequest(req, res) {
   // Create operation context for logging
   const ctx = new operationContext.Context();
   ctx.initFromRequest(req);
+  const startDate = new Date();
+  let success = false;
 
   try {
     ctx.logger.info('Start proxyRequest');
@@ -260,6 +264,7 @@ async function proxyRequest(req, res) {
 
     // Use pipeline to pipe the response data to the client
     await pipeline(result.stream, res);
+    success = true;
 
   } catch (error) {
     ctx.logger.error(`proxyRequest: AI API request error: %s`, error);
@@ -278,6 +283,10 @@ async function proxyRequest(req, res) {
       });
     }
     } finally {
+      // Record the time taken for the proxyRequest in StatsD (skip cors requests and errors)
+      if (clientStatsD && success) {
+        clientStatsD.timing('coauth.aiProxy', new Date() - startDate);
+      }
       ctx.logger.info('End proxyRequest');
     }
 }
diff --git a/DocService/sources/canvasservice.js b/DocService/sources/canvasservice.js
index 1926a576..a807e819 100644
--- a/DocService/sources/canvasservice.js
+++ b/DocService/sources/canvasservice.js
@@ -651,7 +651,7 @@ function* commandSendMailMerge(ctx, cmd, outputData) {
   }
 }
 let commandSfctByCmd = co.wrap(function*(ctx, cmd, opt_priority, opt_expiration, opt_queue, opt_initShardKey) {
-  var selectRes = yield taskResult.select(ctx, cmd.getDocId());
+  var selectRes = yield taskResult.selectWithCache(ctx, cmd.getDocId());
   var row = selectRes.length > 0 ? selectRes[0] : null;
   if (!row) {
     return false;
@@ -1807,7 +1807,7 @@ exports.saveFromChanges = function(ctx, docId, statusInfo, optFormat, opt_userId
       //we do a select, because during the timeout the information could change
       var selectRes = yield taskResult.select(ctx, docId);
       var row = selectRes.length > 0 ? selectRes[0] : null;
-      if (row && row.status == commonDefines.FileStatus.SaveVersion && row.status_info == statusInfo) {
+      if (row && row.status == commonDefines.FileStatus.SaveVersion && row.status_info == statusInfo && row.callback) {
         if (null == optFormat) {
           optFormat = changeFormatByOrigin(ctx, row, constants.AVS_OFFICESTUDIO_FILE_OTHER_OOXML);
         }
@@ -1837,6 +1837,10 @@ exports.saveFromChanges = function(ctx, docId, statusInfo, optFormat, opt_userId
           yield docsCoServer.editorStat.addShutdown(redisKeyShutdown, docId);
         }
         ctx.logger.debug('AddTask saveFromChanges');
+      } else if(row && !row.callback) {
+        ctx.logger.debug('saveFromChanges empty callback: %s', docId);
+        yield docsCoServer.cleanDocumentOnExitNoChangesPromise(ctx, docId, opt_userId, opt_userIndex, false, true);
+        //todo restore status
       } else {
         if (row) {
           ctx.logger.debug('saveFromChanges status mismatch: row: %d; %d; expected: %d', row.status, row.status_info, statusInfo);
diff --git a/DocService/sources/taskresult.js b/DocService/sources/taskresult.js
index 4a5fd6be..96d634be 100644
--- a/DocService/sources/taskresult.js
+++ b/DocService/sources/taskresult.js
@@ -98,7 +98,20 @@ TaskResultData.prototype.completeDefaults = function() {
 function upsert(ctx, task) {
   return sqlBase.upsert(ctx, task);
 }
-
+/**
+ * Return TaskResult rows for docId, caching the last query result on ctx.taskResultCache or fetching from the database.
+ * @param {object} ctx
+ * @param {string} docId
+ * @returns {Promise<Array<object>>}
+ */
+async function selectWithCache(ctx, docId) {
+  //todo merge with select and remove on update
+  if (ctx.taskResultCache && ctx.taskResultCache[0].id === docId) {
+    return ctx.taskResultCache;
+  }
+  ctx.taskResultCache = await select(ctx, docId);
+  return ctx.taskResultCache;
+}
 function select(ctx, docId) {
   return new Promise(function(resolve, reject) {
     let values = [];
@@ -316,6 +329,7 @@ function removeIf(ctx, mask) {
 exports.TaskResultData = TaskResultData;
 exports.upsert = upsert;
 exports.select = select;
+exports.selectWithCache = selectWithCache;
 exports.update = update;
 exports.updateIf = updateIf;
 exports.restoreInitialPassword = restoreInitialPassword;