Hi Aleix Try throwing the result of json->SCM away: (let ((a (call-with...))) 1). Then you can run a (gc) between runs. If the GC time increases then, maybe guile cannot release the memory?? I don't know, but there is some shared substring thing going on in guile, even though I think string-append doesn't do that.
Nice to see that my suggestions worked! -- Linus Björnstam On Wed, 22 Apr 2020, at 00:03, Aleix Conchillo Flaqué wrote: > Hi, > > I was trying to get some guile-json performance times loading large > JSON file. However, I'm getting increasing numbers at each run, so I'm > wondering if I'm doing something wrong. Below you can see how the first > run took 19.95s and then running the same command kept increasing. > > I'm running Guile 2.2.7 on macOS Catalina 10.15.3. > > scheme@(guile-user)> (use-modules (json)) > scheme@(guile-user)> ,t (define a (call-with-input-file > "/Users/aleix/Downloads/large-file.json" (lambda (port) (json->scm > port)))) > ;; 19.956429s real time, 87.100982s run time. 75.270202s spent in GC. > ;; 26.173179s real time, 143.645265s run time. 131.022631s spent in GC. > ;; 28.193926s real time, 154.758375s run time. 141.697236s spent in GC. > ;; 29.044218s real time, 160.745984s run time. 147.449073s spent in GC. > ;; 30.480873s real time, 170.855527s run time. 157.332793s spent in GC. > ;; 30.555700s real time, 172.938278s run time. 159.468737s spent in GC. > ;; 32.190478s real time, 172.807551s run time. 158.905645s spent in GC. > > The good news is that I have applied a suggestion from Linus Björnstam > that reduces times by half (considering the first run above). The > suggestion was to use string ports instead of string-append. And > interestingly this time, time executions remain around the same value: > > scheme@(guile-user)> ,t (define a (call-with-input-file > "/Users/aleix/Downloads/large-file.json" (lambda (port) (json->scm > port)))) > ;; 9.099597s real time, 17.239176s run time. 9.309819s spent in GC. > ;; 9.927868s real time, 20.855859s run time. 12.528727s spent in GC. > ;; 8.981248s real time, 15.043991s run time. 7.050269s spent in GC. > ;; 9.055893s real time, 15.400981s run time. 7.383187s spent in GC. > ;; 9.055850s real time, 15.261824s run time. 7.239188s spent in GC. > ;; 9.315239s real time, 15.231889s run time. 7.005570s spent in GC. > ;; 9.106168s real time, 14.987678s run time. 6.915028s spent in GC. > ;; 9.175142s real time, 14.471324s run time. 6.302749s spent in GC. > ;; 8.966537s real time, 14.400318s run time. 6.412858s spent in GC. > > JSON test data obtained from: > > https://github.com/json-iterator/test-data/blob/master/large-file.json > > Best, > > Aleix