Index: openacs-4/packages/xotcl-request-monitor/xotcl-request-monitor.info
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-request-monitor/xotcl-request-monitor.info,v
diff -u -N -r1.12 -r1.13
--- openacs-4/packages/xotcl-request-monitor/xotcl-request-monitor.info	23 Mar 2018 22:56:43 -0000	1.12
+++ openacs-4/packages/xotcl-request-monitor/xotcl-request-monitor.info	4 Aug 2018 18:55:48 -0000	1.13
@@ -8,7 +8,7 @@
     <singleton-p>t</singleton-p>
     <auto-mount>request-monitor</auto-mount>
 
-    <version name="0.50" url="http://media.wu-wien.ac.at/download/xotcl-request-monitor-0.50.apm">
+    <version name="0.51" url="http://media.wu-wien.ac.at/download/xotcl-request-monitor-0.51.apm">
         <owner url="mailto:neumann@wu-wien.ac.at">Gustaf Neumann</owner>
         <vendor url="http://wu.ac.at">WU Vienna</vendor>
         <summary>Request Monitor with user tracking functionality</summary>
@@ -34,7 +34,7 @@
         <license>BSD-Style</license>
         <maturity>2</maturity>
 
-        <provides url="xotcl-request-monitor" version="0.50"/>
+        <provides url="xotcl-request-monitor" version="0.51"/>
 	<requires url="acs-kernel" version="5.9.1"/>
         <requires url="xotcl-core" version="0.122"/>
 
@@ -45,7 +45,7 @@
             <parameter datatype="string"  min_n_values="1"
 		       max_n_values="1"  name="do_track_activity"
 		       default="off" description="turn activity monitoring on or off (default off)"/>
-            <parameter datatype="string"  min_n_values="1"  max_n_values="1"  name="hide-requests"  default="*.css *.ico" description="List of glob patterns to be used for hiding entries from request lists. Only requests that do not match any of these patterns are displayed unless all requests are forced. Affected pages:   - stat-details (list of all recorded urls with timings) - last-requests (tracking activity of a user)
+            <parameter datatype="string"  min_n_values="1"  max_n_values="1"  name="hide-requests"  default="*.css *.ico" description="List of glob patterns to be used for hiding entries from request lists. Only requests that do not match any of these patterns are displayed unless all requests are forced. Affected pages:   - stat-details (list of all recorded URLs with timings) - last-requests (tracking activity of a user)
 "/>
             <parameter datatype="number"  min_n_values="1"  max_n_values="1"  name="max-stats-elements"  default="5" description="Number of highest data points in the reporting period. The default of 5 will e.g. show you the top 5 times of requests per minute, hour aso."/>
             <parameter datatype="number"  min_n_values="1"  max_n_values="1"  name="max-url-stats"  default="100" description="Number of URL entries to be kept in the detailed view of the request statistics"/>
Index: openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-init.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-init.tcl,v
diff -u -N -r1.8 -r1.9
--- openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-init.tcl	7 Aug 2017 23:48:30 -0000	1.8
+++ openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-init.tcl	4 Aug 2018 18:55:48 -0000	1.9
@@ -15,15 +15,34 @@
   ad_register_filter -priority 1000 postauth POST * throttle
 }
 
-# check if we are running under oacs; if not, provide 
-# minimal compatibility code
+#
+# Check if we are running under OpenACS; if not, provide 
+# minimal compatibility code.
+#
 if {[info commands ad_conn] eq ""} {
-  # otherwise provide alias for ad_conn and dummy for ad_get_user_id
+  #
+  # Otherwise provide alias for "ad_conn"
+  #
   interp alias {} ad_conn {} ns_conn
-  ### this is probably not sufficient to do something useful...
 }
 
+#
+# When activity tracking is on, and we have a recent version of
+# NaviServer, then "::xo::job_dequeue" is defined. We define a
+# scheduled proc that runs every 61 seconds the executes the collected
+# cmd in the background. This version produces substantially less locks
+# on busy servers and reduces latency for the client.
+#
+set do_track_activity [parameter::get_from_package_key \
+                           -package_key "xotcl-request-monitor" \
+                           -parameter do_track_activity \
+                           -default false]
+if {$do_track_activity && [info commands ::xo::job_dequeue] ne ""} {
+  nsv_set request_monitor jobs {}
+  ad_schedule_proc -thread t 61 ::xo::job_dequeue
+}
 
+
 # Local variables:
 #    mode: tcl
 #    tcl-indent-level: 2
Index: openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl,v
diff -u -N -r1.58 -r1.59
--- openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl	26 Jul 2018 17:11:15 -0000	1.58
+++ openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl	4 Aug 2018 18:55:48 -0000	1.59
@@ -845,13 +845,7 @@
     set :user_in_community($key) $data
     #ns_log notice "=== user $key left community $community_id at $now reason $reason after $seconds seconds clicks $clicks"
     if {[do_track_activity] && $seconds > 0} {
-      #set t0 [clock milliseconds]
-      ns_job queue -detached async-cmd \
-          [list ::xo::request_monitor_record_community_activity $key $pa $community_id $seconds $clicks $reason]
-      #set t1 [clock milliseconds]
-      #if {$t1 - $t0 > 500} {
-      #  ns_log warning "request_monitor_record_community_activity left_community slow, can lead to filter time >1sec: total time [expr {$t1 - $t0}]"
-      #}
+      xo::job_enqueue [list ::xo::request_monitor_record_community_activity $key $pa $community_id $seconds $clicks $reason]
     }
   }
 
@@ -871,13 +865,7 @@
     }
     ns_log notice "=== user $key left system at $now reason $reason after $seconds seconds clicks $clicks"
     if {[do_track_activity] && $seconds > 0} {
-      #set t0 [clock milliseconds]
-      ns_job queue -detached async-cmd \
-          [list ::xo::request_monitor_record_activity $key $pa $seconds $clicks $reason]
-      #set t1 [clock milliseconds]
-      #if {$t1 - $t0 > 500} {
-      #  ns_log warning "::xo::request_monitor_record_activity left_system slow, can lead to filter time >1sec: total time [expr {$t1 - $t0}]"
-      #}
+      xo::job_enqueue [list ::xo::request_monitor_record_activity $key $pa $seconds $clicks $reason]
     }
     unset -nocomplain :user_in_community($key) :refcount($key) :pa($key) :expSmooth($key) :switches($key)
   }
@@ -1051,7 +1039,7 @@
     }
 
     #
-    # The array "urls" keeps triples of time stamps, urls and peer
+    # The array "urls" keeps triples of time stamps, URLs and peer
     # addresses per user.
     #
     lappend :urls($key) [list ${:point_in_time} $url $pa]
@@ -1635,10 +1623,46 @@
 }
 
 namespace eval ::xo {
+  
   proc is_ip {key} {
     expr { [string match "*.*" $key] || [string match "*:*" $key] }
   }
 
+  #
+  # Check, if we have a NaviServer with the atomic ns_set operation
+  # with the "-reset" option
+  #
+  #    "nsv_set ?-default? ?-reset? ?--? array key ?value?"
+  #
+  # available. If so, implement an async job-queue with ltttle
+  # overhead based on it.
+  #
+  catch {nsv_set} errMsg
+  if {[string match *-reset* $errMsg]} {
+    #
+    # Yes, we have the "-reset" option.
+    #
+    proc job_enqueue {cmd} {
+      nsv_lappend request_monitor jobs $cmd
+    }
+    
+    proc job_dequeue {} {
+      foreach cmd [nsv_set -reset request_monitor jobs {}] {
+        {*}$cmd
+      }
+    }
+
+  } else {
+    #
+    # Older version of NaviServer, so the classic approach via "ns_job
+    # queue -detached async-cmd ...."
+    #
+    proc job_enqueue {cmd} {
+      ns_job queue -detached async-cmd $cmd
+    }
+  }
+  
+
   proc request_monitor_record_activity {key pa seconds clicks reason} {
     if {[::xo::is_ip $key]} {
       set user_id -1
Index: openacs-4/packages/xotcl-request-monitor/www/last100.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-request-monitor/www/last100.tcl,v
diff -u -N -r1.11 -r1.12
--- openacs-4/packages/xotcl-request-monitor/www/last100.tcl	27 Jun 2018 16:24:27 -0000	1.11
+++ openacs-4/packages/xotcl-request-monitor/www/last100.tcl	4 Aug 2018 18:55:48 -0000	1.12
@@ -46,7 +46,7 @@
   }
 
   #
-  # Provide the urls only to admins as links.
+  # Provide the URLs only to admins as links.
   #
   # First of all, it is questionable, whether this page should be
   # public. However, when this page is public, and a spider
Index: openacs-4/packages/xotcl-request-monitor/www/stat-details.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-request-monitor/www/stat-details.tcl,v
diff -u -N -r1.12 -r1.13
--- openacs-4/packages/xotcl-request-monitor/www/stat-details.tcl	29 Jun 2018 17:27:19 -0000	1.12
+++ openacs-4/packages/xotcl-request-monitor/www/stat-details.tcl	4 Aug 2018 18:55:48 -0000	1.13
@@ -49,7 +49,7 @@
 set full_stat [list]
 if {$with_param == 0} {
   # without parameter
-  # add up same urls
+  # add up same URLs
   array unset aggr_stat
   foreach l $stat {
     lassign $l url time cnt