ZippyJSON is slower than Apple JSONDecoder sometimes about zippyjson

[lamtev]

No, project scheme was configured for debug. And this is why ZippyJSON wasn't as fast as expected. Switching to release configuration causes new results:

JSON size             : ~3 kb
ZippyJSON             : 8.7535e-05 s
Apple                 : 0.000255455 s
Boost (or degradation): ~2.9183183869309426x
------------------------------------------
JSON size             : ~34 kb
ZippyJSON             : 0.000346693 s
Apple                 : 0.001307078 s
Boost (or degradation): ~3.7701309227472137x
------------------------------------------
JSON size             : ~349 kb
ZippyJSON             : 0.003042385 s
Apple                 : 0.013147255 s
Boost (or degradation): ~4.321364653060018x
------------------------------------------
JSON size             : ~3497 kb
ZippyJSON             : 0.031167016 s
Apple                 : 0.135234702 s
Boost (or degradation): ~4.339032713301781x
------------------------------------------

[michaeleisel]

Hi, I'm getting a speedup of at least 3x for all three of those JSON payloads on my iPhone XS. It's iOS 13.1.1, not 13.3.1, but upgrading is a pain and it looks like the last change to Swift's JSONDecoder was in May 2019. Can you send me a zipped Xcode project that does the benchmarking, and the results that it printed to stdout for you? Or at least, a Github gist of the code you used. FYI here is mine: https://gist.github.com/michaeleisel/e2414e93a73601c7e1f99733f8f96a42

[lamtev]

Hi! Thanks for the quick response!

I can see a speedup on simulator, but unfortunately not on real device.

There is a zip archive of my xcode project: ZippyJSONPerformanceIssueDemo.zip

Benchmarking code is in AppDelegate.swift
Parsing duration is measured using DispatchTime.now().

On my iPhone XS i usually get results like that:

JSON size             : ~3 kb
ZippyJSON             : 0.000589531 s
Apple                 : 0.000176595 s
Boost (or degradation): ~0.2995516775199269x
------------------------------------------
JSON size             : ~34 kb
ZippyJSON             : 0.001565232 s
Apple                 : 0.001308632 s
Boost (or degradation): ~0.8360626411931266x
------------------------------------------
JSON size             : ~349 kb
ZippyJSON             : 0.015194142 s
Apple                 : 0.013064061 s
Boost (or degradation): ~0.8598090632560891x
------------------------------------------
JSON size             : ~3497 kb
ZippyJSON             : 0.152393242 s
Apple                 : 0.131946975 s
Boost (or degradation): ~0.8658321935299466x
------------------------------------------

[michaeleisel]

Are you compiling for release? Are you adding any build settings that can slow things down, eg address sanitizer?

[ACFancy]

@lamtev why you close this issue? That problem was solved?

[ACFancy]

@michaeleisel why should use release build configuration?

[michaeleisel]

The release configuration applies optimizations that make it much faster. When your users are using the app, it should be built for release, so that configuration is what matters most