diff --git a/checkin_notes b/checkin_notes
index 346f4fcff1..ce067303b0 100755
--- a/checkin_notes
+++ b/checkin_notes
@@ -315,3 +315,16 @@ David  11 Jan 2006
 
     sched/
         file_upload_handler.C
+
+David  11 Jan 2006
+    - Core client: add a flow control mechanism for the case where
+        output files are generated faster than they can be uploaded
+        (otherwise we'll fill up the disk).
+        The mechanism: don't start new results for a project
+        that has > 2 uploads in progress.
+        Note: this actually happens with Cunning Plan
+        (5 MB output files, 60 sec CPU) over a DSL line
+
+    client/
+        client_types.h
+        cs_apps.C
diff --git a/client/client_types.h b/client/client_types.h
index 9bad5addc7..be63938215 100644
--- a/client/client_types.h
+++ b/client/client_types.h
@@ -274,6 +274,9 @@ public:
         // project in the current scheduling period (secs)
     struct RESULT *next_runnable_result;
         // the next result to run for this project
+    int nactive_uploads;
+        // number of file uploads in progress.
+        // Don't start new results if these exceeds 2.
 
     double work_request;
         // the unit is "normalized CPU seconds",
diff --git a/client/cs_apps.C b/client/cs_apps.C
index 35291ee3b7..97fe102548 100644
--- a/client/cs_apps.C
+++ b/client/cs_apps.C
@@ -285,6 +285,10 @@ void CLIENT_STATE::assign_results_to_projects() {
         project = rp->project;
         if (project->next_runnable_result) continue;
 
+        // don't start results if > 2 uploads in progress
+        //
+        if (project->nactive_uploads > 2) continue;
+
         project->next_runnable_result = rp;
     }
 
@@ -554,10 +558,17 @@ bool CLIENT_STATE::schedule_cpus() {
     //
     for (i=0; i<projects.size(); i++) {
         projects[i]->next_runnable_result = NULL;
+        projects[i]->nactive_uploads = 0;
     }
     for (i=0; i<results.size(); i++) {
         results[i]->already_selected = false;
     }
+    for (i=0; i<file_xfers->file_xfers.size(); i++) {
+        FILE_XFER* fxp = file_xfers->file_xfers[i];
+        if (fxp->is_upload) {
+            fxp->fip->project->nactive_uploads++;
+        }
+    }
 
     set_scheduler_modes();
     adjust_debts();