Megatest

;;     along with Megatest.  If not, see <http://www.gnu.org/licenses/>.
;;

(declare (unit servermod))

(declare (uses commonmod))
(declare (uses configfmod))

(declare (uses debugprint))
(declare (uses mtargs))

(module servermod
	*



	
(use (srfi 18) extras s11n)
(use srfi-1 posix regex regex-case srfi-69 hostinfo md5 message-digest)
(use directory-utils posix-extras matchable utils)
(use spiffy uri-common intarweb http-client spiffy-request-vars)

(import commonmod






	configfmod
	debugprint
	(prefix mtargs args:))



(include "common_records.scm")
(include "db_records.scm")

(define (server:make-server-url hostport)
  (if (not hostport)
      #f

    (debug:print 0 *default-log-port* "INFO: starting server at " (common:human-time))
    (system (conc "nbfake " cmdln))
    (unsetenv "TARGETHOST_LOGF")
    ;; (if (get-environment-variable "TARGETHOST")(unsetenv "TARGETHOST"))
    (thread-join! log-rotate)
    (pop-directory)))

;; given a path to a server log return: host port startseconds server-id
;; any changes to number of elements returned by this fuction will dirctly affect server:record->url,server:record->id,server:kill,server:get-num-alive which use match let 
;; example of what it's looking for in the log file:
;;     SERVER STARTED: 10.38.175.67:50216 AT 1616502350.0 server-id: 4907e90fc55c7a09694e3f658c639cf4 

(define (server:logf-get-start-info logf)
  (let ((server-rx    (regexp "^SERVER STARTED: (\\S+):(\\d+) AT ([\\d\\.]+) server-id: (\\S+) pid: (\\d+)")) ;; SERVER STARTED: host:port AT timesecs server id
        (dbprep-rx    (regexp "^SERVER: dbprep"))
        (dbprep-found 0)
	(bad-dat      (list #f #f #f #f #f)))
    (handle-exceptions

			    ((_ host port start server-id pid)
			     (list host
				   (string->number port)
				   (string->number start)
				   server-id
				   (string->number pid)))
			    (else
			     (debug:print 0 *current-log-port* "ERROR: did not recognise SERVER line info "mlst)
			     bad-dat))))
	       (begin 
		 (if dbprep-found
		     (begin
		       (debug:print-info 2 *default-log-port* "Server is in dbprep at " (common:human-time))
		       (thread-sleep! 0.5)) ;; was 25 sec but that blocked things from starting?
		     (debug:print-info 0 *default-log-port* "Unable to get server info from " logf " at " (seconds->time-string (current-seconds))))
		 bad-dat))))))))

;; ;; get a list of servers from the log files, with all relevant data
;; ;; ( mod-time host port start-time pid )
;; ;;
;; (define (server:get-list areapath #!key (limit #f))
;;   (let ((fname-rx    (regexp "^(|.*/)server-(\\d+)-(\\S+).log$"))
;; 	(day-seconds (* 24 60 60)))
;;     ;; if the directory exists continue to get the list
;;     ;; otherwise attempt to create the logs dir and then
;;     ;; continue
;;     (if (if (directory-exists? (conc areapath "/logs"))
;; 	    '()
;; 	    (if (file-write-access? areapath)
;; 		(begin
;; 		  (condition-case
;; 		   (create-directory (conc areapath "/logs") #t)
;; 		   (exn (i/o file)(debug:print 0 *default-log-port* "ERROR: Cannot create directory at " (conc areapath "/logs")))
;; 		   (exn ()(debug:print 0 *default-log-port* "ERROR: Unknown error attemtping to get server list. exn=" exn)))
;; 		  (directory-exists? (conc areapath "/logs")))
;; 		'()))
;; 
;;         ;; Get the list of server logs.
;; 	(let* (
;;                ;; For some reason, when I uncomment the below line, ext-tests sometimes starts 1000's of servers.
;;                ;; (exiting-servers (system (conc "bash -c 'rm -f `grep -il exiting " areapath "/logs/server-*-*.log 2> /dev/null`'")))
;;                (server-logs   (glob (conc areapath "/logs/server-*-*.log")))
;; 	       (num-serv-logs (length server-logs)))
;; 	  (if (or (null? server-logs) (= num-serv-logs 0))
;;               (let ()
;;                  (debug:print 2  *default-log-port* "There are no servers running at " (common:human-time))
;; 	         '()
;;               )
;; 	      (let loop ((hed  (string-chomp (car server-logs)))
;; 			 (tal  (cdr server-logs))
;; 			 (res '()))
;; 		(let* ((mod-time  (handle-exceptions
;; 				   exn
;; 				   (begin
;; 				     (debug:print 0 *default-log-port* "server:get-list: failed to get modification time on " hed ", exn=" exn)
;; 				     (current-seconds)) ;; 0
;; 				   (file-modification-time hed))) ;; default to *very* old so log gets ignored if deleted
;; 		       (down-time (- (current-seconds) mod-time))
;; 		       (serv-dat  (if (or (< num-serv-logs 10)
;; 				  	  (< down-time 900)) ;; day-seconds))
;; 				      (server:logf-get-start-info hed)
;; 				      '())) ;; don't waste time processing server files not touched in the 15 minutes if there are more than ten servers to look at
;; 		       (serv-rec (cons mod-time serv-dat))
;; 		       (fmatch   (string-match fname-rx hed))
;; 		       (pid      (if fmatch (string->number (list-ref fmatch 2)) #f))
;; 		       (new-res  (if (null? serv-dat)
;; 				     res
;; 				     (cons (append serv-rec (list pid)) res)))) ;; any changes to number of elements in new-res will dirctly affect server:record->url,server:record->id,server:kill,server:get-num-alive which uses match let 
;; 		  (if (null? tal)
;; 		      (if (and limit
;; 			       (> (length new-res) limit))
;; 			  new-res ;; (take new-res limit)  <= need intelligent sorting before this will work
;; 			  new-res)
;; 		      (loop (string-chomp (car tal)) (cdr tal) new-res)))))))))

#;(define (server:get-num-alive srvlst)
  (let ((num-alive 0))
    (for-each
     (lambda (server)
        (handle-exceptions
          exn
         (begin 
          (debug:print-info 0 *default-log-port*  "Unable to get server start-time and/or mod-time from " server ", exn=" exn))
       (match-let (((mod-time host port start-time server-id pid)
		    server))
	 (let* ((uptime  (- (current-seconds) mod-time))
		(runtime (if start-time
			     (- mod-time start-time)
			     0)))
	   (if (< uptime 5)(set! num-alive (+ num-alive 1)))))))
     srvlst)
    num-alive))

;; ;; given a list of servers get a list of valid servers, i.e. at least
;; ;; 10 seconds old, has started and is less than 1 hour old and is
;; ;; active (i.e. mod-time < 10 seconds
;; ;;
;; ;; mod-time host port start-time pid
;; ;;
;; ;; sort by start-time descending. I.e. get the oldest first. Young servers will thus drop off
;; ;; and servers should stick around for about two hours or so.
;; ;;
;; (define (server:get-best srvlst)
;;   (let* ((nums (server:get-num-servers))
;; 	 (now  (current-seconds))
;; 	 (slst (sort
;; 		(filter (lambda (rec)
;; 			  (if (and (list? rec)
;; 				   (> (length rec) 2))
;; 			      (let ((start-time (list-ref rec 3))
;; 				    (mod-time   (list-ref rec 0)))
;; 				;; (print "start-time: " start-time " mod-time: " mod-time)
;; 				(and start-time mod-time
;; 				     (> (- now start-time) 0)    ;; been running at least 0 seconds
;; 				     (< (- now mod-time)   16)   ;; still alive - file touched in last 16 seconds
;; 				     (or (not (configf:lookup *configdat* "server" "runtime")) ;; skip if not set
;; 					 (< (- now start-time)       
;; 					    (+ (- (string->number (configf:lookup *configdat* "server" "runtime"))
;; 					       180)
;; 					    (random 360)))) ;; under one hour running time +/- 180
;; 				     ))
;; 			      #f))
;; 			srvlst)
;; 		(lambda (a b)
;; 		  (< (list-ref a 3)
;; 		     (list-ref b 3))))))
;;     (if (> (length slst) nums)
;; 	(take slst nums)
;; 	slst)))

;; ;; switch from server:get-list to server:get-servers-info
;; ;;
;; (define (server:get-first-best areapath)
;;   (let ((srvrs (server:get-best (server:get-list areapath))))
;;     (if (and srvrs
;; 	     (not (null? srvrs)))
;; 	(car srvrs)
;; 	#f)))
;; 
;; (define (server:get-rand-best areapath)
;;   (let ((srvrs (server:get-best (server:get-list areapath))))
;;     (if (and (list? srvrs)
;; 	     (not (null? srvrs)))
;; 	(let* ((len (length srvrs))
;; 	       (idx (random len)))
;; 	  (list-ref srvrs idx))
;; 	#f)))

(define (server:record->id servr)
  (handle-exceptions
   exn
   (begin 
     (debug:print-info 0 *default-log-port*  "Unable to get server id from " servr ", exn=" exn)     
   #f)

   #f)
  (match-let (((host port start-time server-id pid)
	       servr))
    (if (and host port)
	(conc host ":" port)
	#f))))


;; if server-start-last exists, and wasn't old enough, wait <idle time> + 1, then call this function recursively until it is old enough.
;; if it is old enough, overwrite it and wait 0.25 seconds.
;; if it then has the wrong server key, wait <idle time> + 1 and call this function recursively.
;;
#;(define (server:wait-for-server-start-last-flag areapath)
  (let* ((start-flag (conc areapath "/logs/server-start-last"))
	 ;;; THIS INTERACTS WITH [server] timeout. Suggest using 0.1 or above for timeout (6 seconds)
	 (idletime    (configf:lookup-number *configdat* "server" "idletime" default: 4))
	 (server-key (conc (get-host-name) "-" (current-process-id))))
    (if (file-exists? start-flag)
	(let* ((fmodtime (file-modification-time start-flag))
	       (delta    (- (current-seconds) fmodtime))
	       (old-enough   (> delta idletime))
               (new-server-key ""))
          ;; write start-flag file, wait 0.25s, then if previously the start-flag file was older than <idletime> seconds, and the new file still has the same server key as you just wrote, return #t.
	  ;; the intention is to make sure nfs can read the file we just wrote, and make sure it was written by us, and not another process.
           (if (and old-enough
		    (begin
                      (debug:print-info 2 *default-log-port* "Writing " start-flag)
		      (with-output-to-file start-flag (lambda () (print server-key)))
		      (thread-sleep! 0.25)
		      (set! new-server-key (with-input-from-file start-flag (lambda () (read-line))))
		      (equal? server-key new-server-key)))
	       #t
               ;; If either of the above conditions is not true, print a "Gating server start" message, wait <idle-time> + 1, then call this function recursively. 
	       (begin
		 (debug:print-info 0 *default-log-port* "Gating server start, last start: "
				   (seconds->time-string fmodtime) ", time since last start: " delta ", required idletime: " idletime ", gating reason:" (if old-enough "another job started a server" "too soon to start another server"))
		 
		 (thread-sleep! ( + 1 idletime))
		 (server:wait-for-server-start-last-flag areapath)))))))

;; oldest server alive determines host then choose random of youngest
;; five servers on that host
;;
(define (server:get-servers-info areapath)
  ;; (assert *toppath* "FATAL: server:get-servers-info called before *toppath* has been set.")
  (let* ((servinfodir (server:get-servinfo-dir areapath))) ;; (conc *toppath*"/.servinfo")))
    (if (not (file-exists? servinfodir))

	       (debug:print 0 *default-log-port* "WARNING: found old server info file "sfile", removing it.")
	       (handle-exceptions
		   exn
		 (debug:print 0 *default-log-port* "WARNING: failed to delete old server info file "sfile)
		 (delete-file sfile))))))
     sfiles)))

;; would like to eventually get rid of this
;;
(define (common:on-homehost?)
  (if (eq? (rmt:transport-mode) 'http)
      (server:choose-server *toppath* 'home?)
      #t)) ;; there is no homehost for tcp and nfs is always on home so #t should work

;; kind start up of server, wait before allowing another server for a given
;; area to be launched
;;
(define (server:kind-run areapath)
  ;; look for $MT_RUN_AREA_HOME/logs/server-start-last
  ;; and wait for it to be at least <server idletime> seconds old
  ;; (server:wait-for-server-start-last-flag areapath)
  (let loop ()
    (if (> (alist-ref 'adj-proc-load (common:get-normalized-cpu-load #f)) 2)
	(begin
	  (if (common:low-noise-print 30 "our-host-load")
	      (debug:print 0 *default-log-port* "WARNING: system load is high, waiting to start server."))
	  (loop))))
  (if (< (server:choose-server areapath 'count) 20)
      (server:run areapath))
  #;(if (not (server:check-if-running areapath)) ;; why try if there is already a server running?
      (let* ((lock-file    (conc areapath "/logs/server-start.lock")))
	(let* ((start-flag (conc areapath "/logs/server-start-last")))
	  (common:simple-file-lock-and-wait lock-file expire-time: 25)
	  (debug:print-info  2 *default-log-port* "server:kind-run: touching " start-flag)
	  (system (conc "touch " start-flag)) ;; lazy but safe
	  (server:run areapath)
	  (thread-sleep! 20) ;; don't release the lock for at least a few seconds. And allow time for the server startup to get to "SERVER STARTED".
	  (common:simple-file-release-lock lock-file)))
      (debug:print-info 0 *default-log-port* "Found server already running. NOT trying to start another.")))

;; this one seems to be the general entry point
;;
(define (server:start-and-wait areapath #!key (timeout 60))
  (let ((give-up-time (+ (current-seconds) timeout)))
    (let loop ((server-info (server:check-if-running areapath))
	       (try-num    0))
      (if (or server-info
	      (> (current-seconds) give-up-time)) ;; server-url will be #f if no server available.
	  (server:record->url server-info)
	  (let* ( (servers (server:choose-server areapath 'all-valid))
                (num-ok (if servers (length (server:choose-server areapath 'all-valid)) 0)))
	    (if (and (> try-num 0)  ;; first time through simply wait a little while then try again
		     (< num-ok 1))  ;; if there are no decent candidates for servers then try starting a new one
		(server:run areapath))
	    (thread-sleep! 5)
	    (loop (server:check-if-running areapath)
		  (+ try-num 1)))))))

(define (server:get-num-servers #!key (numservers 2))
  (let ((ns (string->number
	     (or (configf:lookup *configdat* "server" "numservers") "notanumber"))))
    (or ns numservers)))

;; no longer care if multiple servers are started by accident. older servers will drop off in time.
;;
(define (server:check-if-running areapath) ;;  #!key (numservers "2"))
  (let* ((ns            (server:get-num-servers)) ;; get the setting the for maximum number of servers allowed
	 (servers       (server:choose-server areapath 'best-ten))) ;; (server:get-best (server:get-list areapath))))
    (if (or (and servers
		 (null? servers))
	    (not servers))
	    ;; (and (list? servers)
	    ;;	 (< (length servers) (+ 1 (random ns))))) ;; somewhere between 1 and numservers
        #f
        (let loop ((hed (car servers))
                   (tal (cdr servers)))
          (let ((res (server:check-server hed)))
            (if res
                hed
                (if (null? tal)
                    #f
                    (loop (car tal)(cdr tal)))))))))

;; ping the given server
;;
(define (server:check-server server-record)
  (let* ((server-url (server:record->url server-record))
         (server-id  (server:record->id server-record)) 
         (res        (server:ping server-url server-id)))
    (if res
        server-url
	#f)))

(define (server:kill servr)
  (handle-exceptions
    exn
    (begin 
      (debug:print-info 0 *default-log-port*  "Unable to get host and/or port from " servr ", exn=" exn)     
    #f)
  (match-let (((hostname port start-time server-id pid)
	       servr))
    (tasks:kill-server hostname pid))))

;; ;; called in megatest.scm, host-port is string hostname:port
;; ;;
;; ;; NOTE: This is NOT called directly from clients as not all transports support a client running
;; ;;       in the same process as the server.
;; ;;
;; (define (server:ping host:port server-id #!key (do-exit #f))
;;   (let* ((host-port (cond
;; 		     ((string? host:port)
;; 		      (let ((slst (string-split   host:port ":")))
;; 			(if (eq? (length slst) 2)
;; 			    (list (car slst)(string->number (cadr slst)))
;; 			    #f)))
;; 		     (else
;; 		      #f))))
;;     (cond
;;      ((and (list? host-port)
;; 	   (eq? (length host-port) 2))
;;       (let* ((myrunremote (make-and-init-remote *toppath*))
;; 	     (iface       (car host-port))
;; 	     (port        (cadr host-port))
;; 	     (server-dat  (client:connect iface port server-id myrunremote))
;; 	     (login-res   (rmt:login-no-auto-client-setup myrunremote)))
;; 	(http-transport:close-connections myrunremote)
;; 	(if (and (list? login-res)
;; 		 (car login-res))
;; 	    (begin
;; 	      ;; (print "LOGIN_OK")
;; 	      (if do-exit (exit 0))
;; 	      #t)
;; 	    (begin
;; 	      ;; (print "LOGIN_FAILED")
;; 	      (if do-exit (exit 1))
;; 	      #f))))
;;      (else 
;;       (if host:port
;; 	  (debug:print 0 *default-log-port*  "ERROR: bad host:port "host:port))
;;       (if do-exit
;; 	  (exit 1)
;; 	  #f)))))
;; 
;; ;; run ping in separate process, safest way in some cases
;; ;;
;; (define (server:ping-server ifaceport)
;;   (with-input-from-pipe 
;;    (conc (common:get-megatest-exe) " -ping " ifaceport)
;;    (lambda ()
;;      (let loop ((inl (read-line))
;; 		(res "NOREPLY"))
;;        (if (eof-object? inl)
;; 	   (case (string->symbol res)
;; 	     ((NOREPLY)  #f)
;; 	     ((LOGIN_OK) #t)
;; 	     (else       #f))
;; 	   (loop (read-line) inl))))))
;; 
;; ;; NOT USED (well, ok, reference in rpc-transport but otherwise not used).
;; ;;
;; (define (server:login toppath)
;;   (lambda (toppath)
;;     (set! *db-last-access* (current-seconds)) ;; might not be needed.
;;     (if (equal? *toppath* toppath)
;; 	#t
;; 	#f)))

;; timeout is hms string: 1h 5m 3s, default is 1 minute
;; This is currently broken. Just use the number of hours with no unit.
;; Default is 600 seconds.
;;
(define (server:expiration-timeout)
  (let* ((tmo (configf:lookup *configdat* "server" "timeout")))
    (if (string? tmo)

		     (handle-exceptions
		      exn
		      (debug:print-error 0 *default-log-port* "failed to remove " fullname ", exn=" exn)
		      (delete-file* fullname)))))
	     files)
	    (debug:print-info 0 *default-log-port* "Deleted " (length files) " files from logs, keeping " max-allowed " files."))))))

(define (common:wait-for-homehost-load maxnormload msg)
  (let loop ((start-time (current-seconds))) ;; we saw some instances of this being called before *toppath* was set. This might be an early setup race. This delay should help but it is impossible to test...
    (if (not *toppath*)
	(begin
	  (debug:print 0 *default-log-port* "ERROR: common:wait-for-homehost-load called before *toppath* set.")
	  (thread-sleep! 30)
	  (if (< (- (current-seconds) start-time) 300)
	      (loop start-time)))))
  (case (rmt:transport-mode)
    ((http)
     (let* ((hh-dat (if (common:on-homehost?) ;; if we are on the homehost then pass in #f so the calls are local.
			#f
			(server:choose-server *toppath* 'homehost)))
            (hh     (if hh-dat (car hh-dat) #f)))
       (common:wait-for-normalized-load maxnormload msg hh)))
    (else
     (common:wait-for-normalized-load maxnormload msg (get-host-name)))))
    
;;======================================================================
;; Force a megatest cleanup-db if version is changed and skip-version-check not specified
;; Do NOT check if not on homehost!
;;
(define (common:exit-on-version-changed)
  (if (and *toppath*              ;; do nothing if *toppath* not yet provided
	   (common:on-homehost?))
      (if (common:api-changed?)
	  (let* ((mtconf (conc (get-environment-variable "MT_RUN_AREA_HOME") "/megatest.config"))
                 (dbfile  (conc (get-environment-variable "MT_RUN_AREA_HOME") ".mtdb/main.db"))
                 (read-only (not (file-write-access? dbfile)))
                 (dbstruct (db:setup))) ;; (db:setup-db *dbstruct-dbs* *toppath* #f))) ;;  #t)))
	    (debug:print 0 *default-log-port*
			 "WARNING: Version mismatch!\n"
			 "   expected: " (common:version-signature) "\n"
			 "   got:      " (common:get-last-run-version))
            (cond
             ((get-environment-variable "MT_SKIP_DB_MIGRATE") #t)
             ((and (common:file-exists? mtconf) (common:file-exists? dbfile) (not read-only)
                   (eq? (current-user-id)(file-owner mtconf))) ;; safe to run -cleanup-db
              (debug:print 0 *default-log-port* "   I see you are the owner of megatest.config, attempting to cleanup and reset to new version")
              (handle-exceptions
               exn
               (begin
                 (debug:print 0 *default-log-port* "Failed to switch versions. exn=" exn)
                 (debug:print 0 *default-log-port* " message: " ((condition-property-accessor 'exn 'message) exn))
                 (print-call-chain (current-error-port))
                 (exit 1))
               (common:cleanup-db dbstruct)))
             ((not (common:file-exists? mtconf))
              (debug:print 0 *default-log-port* "   megatest.config does not exist in this area.  Cannot proceed with megatest version migration.")
              (exit 1))
             ((not (common:file-exists? dbfile))
              (debug:print 0 *default-log-port* "   .mtdb/main.db does not exist in this area.  Cannot proceed with megatest version migration.")
              (exit 1))
             ((not (eq? (current-user-id)(file-owner mtconf)))
              (debug:print 0 *default-log-port* "   You do not own .mtdb/main.db in this area.  Cannot proceed with megatest version migration.")
              (exit 1))
             (read-only
              (debug:print 0 *default-log-port* "   You have read-only access to this area.  Cannot proceed with megatest version migration.")
              (exit 1))
             (else
              (debug:print 0 *default-log-port* " to switch versions you can run: \"megatest -cleanup-db\"")
              (exit 1)))))))
;;======================================================================
;;      (begin
;;	(debug:print 0 *default-log-port* "ERROR: cannot migrate version unless on homehost. Exiting.")
;;	(exit 1))))

;;======================================================================
;; E X I T   H A N D L I N G
;;======================================================================

;; (define (common:run-sync?)
;;   (and *toppath*               ;; gate if called before *toppath* is set
;;        (common:on-homehost?)
;;        (args:get-arg "-server")))


(define (std-signal-handler signum)
  ;; (signal-mask! signum)
  (set! *time-to-exit* #t) 
  ;;(debug:print-info 13 *default-log-port* "got signal "signum)
  (debug:print-error 0 *default-log-port* "Received signal " signum " aaa exiting promptly")
  ;; (std-exit-procedure) ;; shouldn't need this since we are exiting and it will be called anyway

  ;; (std-exit-procedure) ;; shouldn't need this since we are exiting and it will be called anyway
  (exit))


(set-signal-handler! signal/int  std-signal-handler)  ;; ^C
(set-signal-handler! signal/term std-signal-handler)
;;======================================================================



;; ideally put all this info into the db, no need to preserve it across moving homehost
;;
;; return list of
;;  ( reachable? cpuload update-time )
(define (common:get-host-info hostname)
  (let* ((loadinfo                         (rmt:get-latest-host-load hostname)) ;; if this host happens to have been recently used by a test reuse the load data
         (load                             (car loadinfo))
         (load-sample-time                 (cdr loadinfo))
         (load-sample-age                  (- (current-seconds) load-sample-time))
         (loadinfo-timeout-seconds         6) ;; this was 20 seconds, seems way too lax. Switch to 6 seconds
         (host-last-update-timeout-seconds 4)
         (host-rec (hash-table-ref/default *host-loads* hostname #f))
         )
    (cond
     ((< load-sample-age loadinfo-timeout-seconds)

      (list #t
            load-sample-time
            load))
     ((and host-rec
           (< (current-seconds) (+ (host-last-update host-rec) host-last-update-timeout-seconds)))
      (list #t

            (host-last-update host-rec)
            (host-last-cpuload host-rec )))
     ((common:unix-ping hostname)


      (list #t
            (current-seconds)
            (alist-ref 'adj-core-load (common:get-normalized-cpu-load hostname)))) ;; this is cheaper than you might think. get-normalized-cpu-load is cached for up to 5 seconds
     (else
      (list #f 0 -1) ;; bad host, don't use!
      ))))

;;======================================================================
;; see defstruct host at top of file.
;;    host: reachable last-update last-used last-cpuload
;;
(define (common:update-host-loads-table hosts-raw)
  (let* ((hosts (filter (lambda (x)
                          (string-match (regexp "^\\S+$") x))
                        hosts-raw)))
    (for-each
     (lambda (hostname)
       (let* ((rec       (let ((h (hash-table-ref/default *host-loads* hostname #f)))
                          (if h
                              h
                              (let ((h (make-host)))
                                (hash-table-set! *host-loads* hostname h)
                                h))))
              (host-info         (common:get-host-info hostname))
              (is-reachable      (car host-info))
              (last-reached-time (cadr host-info))
              (load              (caddr host-info)))
         (host-reachable-set!    rec is-reachable)
         (host-last-update-set!  rec last-reached-time)
         (host-last-cpuload-set! rec load)))
     hosts)))

;;======================================================================
;; DO NOT CALL THIS DIRECTLY. It is called from common:wait-for-normalized-load
;;   count     - count down to zero, at some point we'd give up if the load never drops
;;   num-tries - count down to zero number tries to get numcpus
;;
(define (common:wait-for-cpuload maxnormload numcpus-in

			", normalized effective load: " normalized-effective-load
			))
     ;; overloaded and count expired (i.e. went to zero)
     (else
      (if (> num-tries 0) ;; should be "num-tries-left". 
	  (if (common:low-noise-print 30 (conc (round effective-load) "-load-acceptable-" effective-host))
	      (debug:print 0 *default-log-port* "Load on " effective-host " is acceptable at effective normalized load of "
			   effective-normalized-load "  continuing."))
	  (debug:print 0 *default-log-port* "Load on " effective-host ", "
		       first" could not be retrieved. Giving up and continuing."))))))

;;======================================================================
;; DO NOT CALL THIS DIRECTLY. It is called from common:wait-for-normalized-load
;;
;; (define (common:wait-for-cpuload maxload-in numcpus-in waitdelay #!key (count 1000) (msg #f)(remote-host #f)(force-maxload #f)(num-tries 5))