Megatest

      (let ((db (sqlite3:open-database fname)))
	(sqlite3:set-busy-handler! db (make-busy-timeout 136000))
	(sqlite3:execute db "PRAGMA synchronous = 0;")
	db)
      (let* ((parent-dir   (pathname-directory fname))
	     (dir-writable (file-write-access? parent-dir)))
	(if dir-writable
	    (let ((exists  (file-exists? fname))
		  (lock    (obtain-dot-lock fname 1 5 10))

		  (db      (sqlite3:open-database fname)))
	      (sqlite3:set-busy-handler! db (make-busy-timeout 136000))
	      (sqlite3:execute db "PRAGMA synchronous = 0;")
	      (if (not exists)(initproc db))
	      (release-dot-lock fname)
	      db)
	    (begin
	      (debug:print 0 "ERROR: no such db in non-writable dir " fname)
	      (sqlite3:open-database fname))))))

;; This routine creates the db. It is only called if the db is not already opened
;; 
(define (db:open-rundb dbstruct run-id #!key (attemptnum 0)) ;;  (conc *toppath* "/megatest.db") (car *configinfo*)))
  (let* ((local  (dbr:dbstruct-get-local dbstruct))
	 (rdb    (if local
		     (dbr:dbstruct-get-localdb dbstruct run-id)
		     (dbr:dbstruct-get-inmem dbstruct)))) ;; (dbr:dbstruct-get-runrec dbstruct run-id 'inmem)))
    (if rdb
	rdb
	(let* ((dbpath       (db:dbfile-path run-id)) ;; (conc toppath "/db/" run-id ".db"))
	       (dbexists     (file-exists? dbpath))
	       (inmem        (if local #f (db:open-inmem-db)))
	       (refdb        (if local #f (db:open-inmem-db)))
	       (db           (db:lock-create-open dbpath 
						  (lambda (db)
						    (handle-exceptions
						     exn
						     (begin
						       (release-dot-lock dbpath)
						       (if (> attemptnum 2)
							   (debug:print 0 "ERROR: tried twice, cannot create/initialize db for run-id " run-id ", at path " dbpath)
							   (db:open-rundb dbstruct run-id attemptnum (+ attemptnum 1))))
						     (db:initialize-run-id-db db)
						     (sqlite3:execute 
						      db
						      "INSERT OR IGNORE INTO tests (id,run_id,testname,event_time,item_path,state,status) VALUES (?,?,'bogustest',strftime('%s','now'),'nowherepath','DELETED','n/a');"
						      (* run-id 30000) ;; allow for up to 30k tests per run
						      run-id)
						     ;; do a dummy query to test that the table exists and the db is truly readable
						     (sqlite3:execute db "SELECT * FROM tests WHERE id=?;" (* run-id 30000))
						    )))) ;; add strings db to rundb, not in use yet
	       ;;   )) ;; (sqlite3:open-database dbpath))
	       (olddb        (if *megatest-db*
				 *megatest-db* 
				 (let ((db (db:open-megatest-db)))
				   (set! *megatest-db* db)
				   db)))
	       (write-access (file-write-access? dbpath))

       (let* ((send-recieve (lambda ()
			      (mutex-lock! *http-mutex*)
			      ;; (condition-case (with-input-from-request "http://localhost"; #f read-lines)
			      ;;					       ((exn http client-error) e (print e)))
			      (set! res (handle-exceptions
					 exn
					 (begin
					   (debug:print 0 "WARNING: failure in with-input-from-request to " fullurl ". Killing associated server to allow clean retry.")
					   (debug:print 0 " message: " ((condition-property-accessor 'exn 'message) exn))
					   (hash-table-delete! *runremote* run-id)
					   ;; (tasks:kill-server-run-id run-id)  ;; better to kill the server in the logic that called this routine.
					   #f)
					 (with-input-from-request ;; was dat
					  fullurl 
					  (list (cons 'key "thekey")
						(cons 'cmd cmd)
						(cons 'params params))
					  read-string)))

	       (debug:print-info 1 "db write rate too high, starting a server, count=" count " start=" start " run-id=" run-id " queries-per-second=" queries-per-second)
	       #t)
	     #f))))

;; cmd is a symbol
;; vars is a json string encoding the parameters for the call
;;
(define (rmt:send-receive cmd rid params #!key (attemptnum 0))
  ;; clean out old connections
  (mutex-lock! *db-multi-sync-mutex*)
  (let ((expire-time (- (current-seconds) 60)))
    (for-each 
     (lambda (run-id)
       (let ((connection (hash-table-ref/default *runremote* run-id #f)))
	 (if ;; (and connection 

	(let ((res             (http-transport:client-api-send-receive run-id connection-info cmd jparams)))
	  (http-transport:server-dat-update-last-access connection-info)
	  (if res
	      (db:string->obj res)
	      (let ((new-connection-info (client:setup run-id)))
		(debug:print 0 "WARNING: Communication failed, trying call to http-transport:client-api-send-receive again.")
		(hash-table-delete! *runremote* run-id) ;; don't keep using the same connection

		;; no longer killing the server in http-transport:client-api-send-receive
		;; may kill it here but what are the criteria?
		;; start with three calls then kill server
		(if (eq? attemptnum 3)(tasks:kill-server-run-id run-id))

		(rmt:send-receive cmd run-id params attemptnum: (+ attemptnum 1)))))
	(let ((max-avg-qry (string->number (or (configf:lookup *configdat* "server" "server-query-threshold") "10"))))
	  (debug:print-info 4 "no server and read-only query, bypassing normal channel")
	  ;; (if (rmt:write-frequency-over-limit? cmd run-id)(server:kind-run run-id))
	  (let ((curr-max (rmt:get-max-query-average run-id)))
	    (if (> (cdr curr-max) max-avg-qry)
		(if (common:low-noise-print 10 "start server due to max average query too long")
		      (begin