Posted by The Android Developer Relations group
TL;DR
TikTok serves a variety of person teams. With customers all over the world, it’s inevitable that a few of them expertise community points similar to gradual, intermittent, or costly connectivity. Different customers are utilizing entry degree units with restricted reminiscence and storage. Making certain a superb app expertise in all these situations is paramount. TikTok’s group was capable of considerably enhance their general efficiency by following Android’s efficiency steerage, and using their deep understanding of improvement instruments similar to Android Gradle Plugin and Jetpack libraries. If you wish to learn the way the TikTok group improved their app expertise to realize higher enterprise efficiency, please learn our enterprise article right here.
Intro
TikTok is likely one of the hottest community-driven leisure platforms with 1 billion folks throughout the globe publishing and looking video content material on daily basis.
A various person base naturally means numerous community bandwidth situations and units with totally different display sizes, obtainable reminiscence and processing energy. All customers need a clean, responsive app expertise, regardless of which gadget they use. If the app is gradual to load, or playback will get caught, customers will really feel pissed off and would possibly abandon the app altogether. To keep away from points like these, the TikTok group constantly tracks the general app efficiency by ongoing information monitoring, peer benchmarks, and person surveys.
TikTok is consistently introducing new options. However a fast improve in performance generally results in an upsurge in technical necessities. The engineering group recognized three causes that slowed down the app : janky frames, video playback lag, and community points. To unravel these points, the TikTok group appeared to Android instruments to begin their app enchancment journey.
From Discovery to Resolution
Lowering app startup time, a smoother person expertise with diminished jank and higher video playback expertise have been three main objectives that the group prioritized. In addition they mentioned easy methods to measure the results of efficiency optimization to forestall the prevalence of regression.
1. Quicker startup: refactor startup framework
App startup time is likely one of the metrics in Android Vitals. Ensuring the app startup time is not than the Android Important’s suggestion is one of the best ways to make sure the app masses and begins responding to person exercise as shortly as attainable. The App Startup library is an Android Jetpack library to assist builders initialize app parts merely and effectively.
The group studied the App Startup library in depth and refactored the app’s startup framework to realize on-demand loading and meticulous scheduling of parts. With the intention to additional cut back the execution time of making Views on the principle thread, the group even used a background thread to load View parts asynchronously, thus enhancing the general pace of app startup.
TikTok used Simpleperf to investigate the code execution time, and Android Studio’s Profiler to observe the utilization of sources similar to reminiscence, CPU, and community to optimize I/O, threads, and useful resource locks.
2. Smoother person interface
To make sure a smoother person interface, the group wanted to deal with two challenges: 1) simplify the View hierarchy, in order that the app solely renders what is critical on display, and a couple of) cut back the variety of job executions in every body in order that the app can have a gentle body price.
The TikTok group used the Structure Inspector in Android Studio to pinpoint the pointless structure contents. The structure boundaries of every View are clearly seen within the inspector, so the group can simply simplify the View hierarchy of the interface and cut back extreme and pointless content material drawing.
In lots of circumstances, TikTok used doFrame() to carry out frame-by-frame duties. Attempting to suit an excessive amount of work in a single body will inevitably trigger a jank. TikTok’s strategy was to make use of allocation algorithms to distribute duties into totally different frames to make sure that the applying has a gentle body price.
3. Higher video playback expertise: reuse sources
TikTok customers can create audio and video content material in varied methods, and totally different codecs are used to play various kinds of content material. Android gives the MediaCodec class to assist entry the underlying codec. To additional enhance the pace of video playback, it’s good follow to supply totally different media participant situations for various codecs. The TikTok group created a pool of media participant situations all through the applying to neatly present for varied media contents. They even run every media participant occasion in several threads to reduce interference between each other
Community connection pace is one other contributor to video lag . The group examined totally different options, together with optimizing connections and reusing sockets, and developed algorithms to dynamically modify buffer size when streaming content material to cut back lag throughout playback.
In addition they used on-device video super-resolution to generate high-resolution frames primarily based on low-resolution video content material, additional enhancing the standard of video playback with out rising community strain.
Preloading (loading the subsequent video forward of time) and pre-rendering (rendering the primary body of the video forward of time) are essential parts to make sure that customers have a clean expertise when enjoying a number of movies in succession. TikTok drew a Floor prematurely solely including it into the display when it’s truly wanted, to cut back the strain of drawing it on the spot.
4. Keep away from regressions
The group continues to keep up an in depth understanding of efficiency and works to fine-tune components when mandatory. Fortunately, Android has instruments in place for this actual goal, like Systrace to seize traces so builders can export system actions (together with CPU scheduling, disk actions, and app threads) for detailed evaluation. The group additionally depends closely on instruments like Perfetto and Android Studio CPU profiler to trace the execution time of assorted occasions, particularly for I/O and sophistication loading.
Higher Efficiency, Higher Expertise
TikTok creatively leveraged the Android toolchain to trace, quantify, and optimize their app’s efficiency for its enterprise priorities, leading to improved person expertise and a rise in person satisfaction
The app startup time was diminished by 45%, and the smoothness (the possibility of the body price being decrease than the goal worth) has been optimized by 49%. When enjoying a video, the primary body of the video appeared 41% quicker, and the possibility of video lag was diminished by 27%.
Customers are actually extra keen to make use of TikTok: lively days per person in 30 days elevated by 1percentas did the common of session length. Person surveys and TikTok’s ranking in Google Play additionally present a major improve in person satisfaction.
The Subsequent Stage for TikTok
By continuously optimizing app efficiency and adapting to the newest Android 13 platform, TikTok has created a extra seamless app expertise, encouraging extra customers to find, create, and share the content material they love.
With greater than 250 million lively large-screen Android units globally, the group has additionally been specializing in large-screen units, together with foldable units. By adopting the app to giant screens, the group has introduced a extra immersive expertise to TikTok customers.
To be taught extra about how TikTok optimized its Android app to enhance person expertise and enterprise efficiency, learn the article right here.
Get Steering on Efficiency
To be taught how one can get began to examine, enhance and monitor your app’s efficiency go to our developer information. The quickest manner to enhance your app’s launch pace is by including a baseline profile to your subsequent launch.
