diff options
Diffstat (limited to 'guix/scripts/offload.scm')
| -rw-r--r-- | guix/scripts/offload.scm | 46 |
1 files changed, 23 insertions, 23 deletions
diff --git a/guix/scripts/offload.scm b/guix/scripts/offload.scm index 2e0268020c..bc024a8701 100644 --- a/guix/scripts/offload.scm +++ b/guix/scripts/offload.scm @@ -490,6 +490,7 @@ be read." (define (machine-load machine) "Return the load of MACHINE, divided by the number of parallel builds allowed on MACHINE." + ;; Note: This procedure is costly since it creates a new SSH session. (let* ((session (open-ssh-session machine)) (pipe (open-remote-pipe* session OPEN_READ "cat" "/proc/loadavg")) @@ -510,17 +511,6 @@ allowed on MACHINE." (_ +inf.0))))) ;something's fishy about MACHINE, so avoid it -(define (machine-power-factor m) - "Return a factor that aggregates the speed and load of M. The higher the -better." - (/ (build-machine-speed m) - (+ 1 (machine-load m)))) - -(define (machine-less-loaded-or-faster? m1 m2) - "Return #t if M1 is either less loaded or faster than M2. (This relation -defines a total order on machines.)" - (> (machine-power-factor m1) (machine-power-factor m2))) - (define (machine-lock-file machine hint) "Return the name of MACHINE's lock file for HINT." (string-append %state-directory "/offload/" @@ -548,29 +538,39 @@ defines a total order on machines.)" ;; 5. Release the global machine-choice lock. (with-file-lock (machine-choice-lock-file) - (define machines+slots + (define machines+slots+loads (filter-map (lambda (machine) + ;; Call 'machine-load' from here to make sure it is called + ;; only once per machine (it is expensive). (let ((slot (acquire-build-slot machine))) - (and slot (list machine slot)))) + (and slot + (list machine slot (machine-load machine))))) machines)) (define (undecorate pred) (lambda (a b) (match a - ((machine1 slot1) + ((machine1 slot1 load1) (match b - ((machine2 slot2) - (pred machine1 machine2))))))) - - (let loop ((machines+slots - (sort machines+slots + ((machine2 slot2 load2) + (pred machine1 load1 machine2 load2))))))) + + (define (machine-less-loaded-or-faster? m1 l1 m2 l2) + ;; Return #t if M1 is either less loaded or faster than M2, with L1 + ;; being the load of M1 and L2 the load of M2. (This relation defines a + ;; total order on machines.) + (> (/ (build-machine-speed m1) (+ 1 l1)) + (/ (build-machine-speed m2) (+ 1 l2)))) + + (let loop ((machines+slots+loads + (sort machines+slots+loads (undecorate machine-less-loaded-or-faster?)))) - (match machines+slots - (((best slot) others ...) + (match machines+slots+loads + (((best slot load) others ...) ;; Return the best machine unless it's already overloaded. - (if (< (machine-load best) 2.) + (if (< load 2.) (match others - (((machines slots) ...) + (((machines slots loads) ...) ;; Release slots from the uninteresting machines. (for-each release-build-slot slots) |