Index: openacs-4/packages/xotcl-core/tcl/40-thread-mod-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-core/tcl/40-thread-mod-procs.tcl,v
diff -u -N -r1.20.2.4 -r1.20.2.5
--- openacs-4/packages/xotcl-core/tcl/40-thread-mod-procs.tcl	16 Sep 2021 09:51:55 -0000	1.20.2.4
+++ openacs-4/packages/xotcl-core/tcl/40-thread-mod-procs.tcl	17 Sep 2021 09:27:47 -0000	1.20.2.5
@@ -166,7 +166,7 @@
 
 ::xotcl::THREAD instproc destroy {} {
   :log "destroy called"
-  if {![:persistent] &&
+  if {!${:persistent} &&
       [nsv_exists [self class] [self]]} {
     set tid [nsv_get [self class] [self]]
     set refcount [::thread::release $tid]
@@ -200,19 +200,20 @@
       #:check_blueprint
       #:log "after lock"
       if {![nsv_exists [self class] [self]]} {
-        if {[:lightweight]} {
+        if {${:lightweight}} {
           :log "CREATE lightweight thread"
           set tid [::thread::create -thin]
         } else {
           set tid [::thread::create]
         }
-        if {[:persistent]} {
+        nsv_set [self class] [self] $tid
+        if {${:persistent}} {
           :log "--created new persistent [self class] as $tid pid=[pid]"
         } else {
           :log "--created new [self class] as $tid pid=[pid]"
         }
         #:log "--THREAD DO send [self] epoch = [ns_ictl epoch]"
-        if {[:lightweight]} {
+        if {${:lightweight}} {
         } elseif {![ns_ictl epoch]} {
           #ns_log notice "--THREAD send [self] no epoch"
           # We are during initialization. For some unknown reasons, XOTcl
@@ -224,12 +225,18 @@
         append initcmd ${:initcmd}
         #ns_log notice "INIT $initcmd"
         ::thread::send $tid $initcmd
-        
+
         #
-        # Tell the world about the thread only once it is fully
-        # working to avoid potential race-conditions during startup.
+        # There is a potential race condition during startup on a very
+        # slow/busy system, where the throttle thread can receive
+        # commands, although it is not full initialized. One approach
+        # would be to move the nsv setting of the pid here, where the
+        # thread is fully initialized, .... but unfortunately, this
+        # leads to problems as well. This needs deeper investing,
+        # ... but is not very important, since it is very hard to
+        # reconstruct the problem case.
         #
-        nsv_set [self class] [self] $tid
+        #nsv_set [self class] [self] $tid
       } else {
         set tid [nsv_get [self class] [self]]
       }
@@ -244,7 +251,7 @@
     #
     # This is the first call.
     #
-    if {![:persistent] && ![info exists :recreate]} {
+    if {!${:persistent} && ![info exists :recreate]} {
       #
       # For a shared thread, we do ref-counting through preserve.
       #
@@ -305,7 +312,7 @@
 
 Class create ::xotcl::THREAD::Client -parameter {server {serverobj [self]}}
 ::xotcl::THREAD::Client instproc do args {
-  [:server] do [:serverobj] {*}$args
+  ${:server} do ${:serverobj} {*}$args
 }
 
 ::xo::library source_dependent