Allow the GLOBAL_WINDOWSIZE to be overridden as well.

For installs that really need to limit total responses due to memory issues. Also, fixes a small logic error that could lead to the global windowsize being hit prematurely.
horde · Dec 12, 2015 · ad5b32f · ad5b32f
1 parent 60cf793
commit ad5b32f
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Showing 3 changed files with 66 additions and 22 deletions.
diff --git a/framework/ActiveSync/lib/Horde/ActiveSync/Collections.php b/framework/ActiveSync/lib/Horde/ActiveSync/Collections.php
@@ -77,11 +77,19 @@ class Horde_ActiveSync_Collections implements IteratorAggregate
 
     /**
      * Global WINDOWSIZE
+     * Defaults to 100 (MS-ASCMD 2.2.3.188)
      *
      * @var integer
      */
     protected $_globalWindowSize = 100;
 
+    /**
+     * Flag to indicate we have overridden the globalWindowSize
+     *
+     * @var boolean
+     */
+    protected $_windowsizeOverride = false;
+
     /**
      * Imported changes flag.
      *
@@ -432,11 +440,19 @@ public function getChangesFlag($collection_id)
      * that can be sent (including all collections). This method should be
      * renamed for 3.0
      *
-     * @param integer $window  The windowsize
+     * @param integer $window    The windowsize
+     * @param boolean $override  If true, this value will override any client
+     *                           supplied value.
      */
-    public function setDefaultWindowSize($window)
+    public function setDefaultWindowSize($window, $override = false)
     {
-        $this->_globalWindowSize = $window;
+        if ($override) {
+            $this->_windowsizeOverride = true;
+        }
+
+        if ($override || empty($this->_windowsizeOverride)) {
+            $this->_globalWindowSize = $window;
+        }
     }
 
     public function getDefaultWindowSize()

diff --git a/framework/ActiveSync/lib/Horde/ActiveSync/Request/Sync.php b/framework/ActiveSync/lib/Horde/ActiveSync/Request/Sync.php
@@ -274,6 +274,11 @@ protected function _handle()
 
         $pingSettings = $this->_driver->getHeartbeatConfig();
 
+        // Override the total, per-request, WINDOWSIZE?
+        if (!empty($pingSettings['maximumrequestwindowsize'])) {
+            $this->_collections->setDefaultWindowSize($pingSettings['maximumrequestwindowsize'], true);
+        }
+
         // If this is >= 12.1, see if we want a looping SYNC.
         if ($this->_collections->canDoLoopingSync() &&
             $this->_device->version >= Horde_ActiveSync::VERSION_TWELVEONE &&
@@ -490,13 +495,13 @@ protected function _handle()
                         ? min($collection['windowsize'], $pingSettings['maximumwindowsize'])
                         : $collection['windowsize'];
 
-                    if ((!empty($changecount) && $changecount > $max_windowsize) ||
-                        ($cnt_global + $changecount > $this->_collections->getDefaultWindowSize())) {
+                    if (!empty($changecount) &&
+                        (($changecount > $max_windowsize) || $cnt_global + $max_windowsize > $this->_collections->getDefaultWindowSize())) {
                         $this->_logger->info(sprintf(
-                            '[%s] Sending MOREAVAILABLE. WINDOWSIZE = %d, $changecount = %d, $cnt_global = %d',
-                            $this->_procid, $max_windowsize, $changecount, $cnt_global));
+                            '[%s] Sending MOREAVAILABLE. WINDOWSIZE = %d, $changecount = %d, MAX_REQUEST_WINDOWSIZE = %d, $cnt_global = %d',
+                            $this->_procid, $max_windowsize, $changecount, $this->_collections->getDefaultWindowSize(), $cnt_global));
                         $this->_encoder->startTag(Horde_ActiveSync::SYNC_MOREAVAILABLE, false, true);
-                        $over_window = ($cnt_global + $changecount > $this->_collections->getDefaultWindowSize());
+                        $over_window = ($cnt_global + $max_windowsize > $this->_collections->getDefaultWindowSize());
                     }
 
                     if (!empty($changecount)) {

diff --git a/horde/config/conf.xml b/horde/config/conf.xml
@@ -2392,21 +2392,44 @@
       during each heartbeat.">15</configinteger>
       <configheader>Maximum Collection Window Size</configheader>
       <configdescription>The Maximum Collection Window Size specifies the
-      maximum number of messages that can be sent to the client in a single
-      request before a MOREAVAILABLE flag is sent indicating the remaining
-      messages should be fetched in the next request. This is normally
-      automatically handled by the client but it may be helpful to explicitly
-      limit this if the server is hitting against PHP's memory limit. This is
-      especially true when synchronizing with Outlook, which has an
-      extremely high default window size. If you need to set this, start with
-      a value such as 100 and increase/decrease as necessary after testing. A
-      value of 0 indicates that the client's value will be honored. Setting this
-      to lower values will also make it appear that the client is performing the
-      initial sync quicker, at the expense of needing more server requests.
+      maximum number of messages from a single collection/folder that can be
+      sent to the client in a single request before a MOREAVAILABLE flag is sent
+      (indicating the remaining messages should be fetched in the next request).
+      This is normally automatically handled by the client but it may be helpful
+      to explicitly limit this if the server is hitting against PHP's memory
+      limit. This is especially true when synchronizing with Outlook, which has
+      an extremely high default window size.
+      There is also a per-REQUEST limit that can be enforced. The server will
+      NEVER send more than the per-request value in a single HTTP request. If
+      the server reaches the per-COLLECTION value, but not the per-REQUEST
+      value, a MOREAVAILABLE flag will be sent and processing will move on to
+      the next collection. This continues until the per-request value is
+      reached. So, for example, you may limit the total number of responses per
+      request to 100, but the per-collection limit to 10. This will limit the
+      size of the total response, while allowing more collections to begin to
+      populate sooner. Setting the per-request closer to or equal to the
+      per-collection value will still limit the total number of responses, but
+      it will take more requests to begin to populate each collection.
+      In Outlook, for example, it will take longer for individual email folders
+      to BEGIN to populate during initial sync.
+
+      If you need to set this, start with a total per-REQUEST limit of 100 and
+      increase/decrease as necessary after testing. A value of 0 indicates that
+      the client's value will be honored. Setting the per-REQUEST limit, but
+      leaving the per-COLLECTION limit at 0 will attempt to honor the
+      per-collection limit of the client, while still limiting the total number
+      of responses sent during a single HTTP request.
+
+      Setting this to lower values will also make it appear that the client is
+      performing the initial sync quicker, at the expense of needing more server
+      requests.
       </configdescription>
-      <configinteger name="maximumwindowsize" desc="The Maximum Window Size to
-      use, overriding the client sent value. Set to 0 to use the client value.">
-      0</configinteger>
+      <configinteger name="maximumwindowsize" desc="The Maximum Collection
+      Window Size to use, overriding the client sent value. Set to 0 to use
+      the client value.">0</configinteger>
+      <configinteger name="maximumrequestwindowsize" desc="The Maximum Request
+      Window Size to use, overriding the client sent value. Set to 0 to use the
+      client value.">0</configinteger>
      </configsection>
     </case>
    </configswitch>