Index: db.scm
==================================================================
--- db.scm
+++ db.scm
@@ -4254,10 +4254,52 @@
 	   (conc (current-directory) "/" outputfile)))
      results)
     ;; brutal clean up
     (dbfile:add-dbdat dbstruct #f dbdat)
     (system "rm -rf tempdir")))
+
+;;======================================================================
+;; cached writes stuff
+;;======================================================================
+
+(define (dbfile:add-cached-write dbstruct proc run-id params)
+  (mutex-lock! *cached-writes-mutex*)
+  (let* ((hkey                (cons dbstruct run-id))
+	 (cached-writes-queue (hash-table-ref/default *cached-writes-queues* hkey '())))
+    (hash-table-set! *cached-writes-queues* hkey (cons (list proc params) cached-writes-queue)))
+  (if (not *cached-writes-flag*)
+      (begin
+	(set! *cached-writes-flag* #t)
+	(thread-start! (make-thread
+			(lambda ()
+			  (thread-sleep! 1)
+			  (dbfile:process-cached-writes-queue))))))
+  (mutex-unlock! *cached-writes-mutex*))
+
+(define (db:process-cached-writes-queue)
+  (mutex-lock! *cached-writes-mutex*)
+  (hash-table-for-each
+   *cached-writes-queues*
+   (lambda (hkey writes-list)
+     (let* ((dbstruct (car hkey))
+	    (run-id   (cdr hkey)))
+       (db:with-db
+	dbstruct
+	run-id
+	#t 
+	(lambda (db)
+	  (sqlite3:with-transaction
+	   db
+	   (lambda ()
+	     (for-each
+	      (lambda (queued-write)
+		(match queued-write
+		       ((proc params)(apply proc params))
+		       (else (assert #f "BAD queued-write"))))
+	      writes-list))))))))
+  (set! *cached-writes* #f)
+  (mutex-unlock! *cached-writes-mutex*))
 
 ;; (db:extract-ods-file db "outputfile.ods" '(("sysname" "%")("fsname" "%")("datapath" "%")) "%")
 
 ;;======================================================================
 ;; moving watch dogs here due to dependencies

Index: dbfile.scm
==================================================================
--- dbfile.scm
+++ dbfile.scm
@@ -1438,7 +1438,17 @@
 			    ;; (db:hoh-set! stmt-cache db stmt newstmth)
 			    (hash-table-set! stmt-cache stmt newstmth)
 			    newstmth))))
     (mutex-unlock! *get-cache-stmth-mutex*)
     result))
+
+;;======================================================================
+;; cached writes - run list of procs inside transaction
+;;   NOTE: this only works because we have once database per process
+;;======================================================================
+
+(define *cached-writes-mutex* (make-mutex))
+(define *cached-writes-flag*  #f)
+(define *cached-writes-queues* (make-hash-table)) ;; dbstruct->list of writes
+
 
 )