7 ms·

How removing caching improved mobile performance by 25%

116 points by thijser 10y ago

tyingq 10y ago
Well, specifically removing the html5 offline application cache if you don't need offline functionality. That it causes duplicate requests, and apparently more of them in chrome mobile than other browsers, is interesting though.
- dalanmiller 10y ago
  Agreed ^ this title is a big misleading / clickbaity
  - tyingq 10y ago
    Not sure why they went that way either..."Offline Cache Causes Duplicate Asset Downloads" would have caught my attention just fine.
    - disconnected 10y ago
      Not a web technology expert, but apparently the appcache feature is deprecated (https://developer.mozilla.org/en-US/docs/Web/HTML/Using_the_application_cache https://developer.mozilla.org/en-US/docs/Web/HTML/Using_the_...) and this dead horse has already been beaten to... er, death? before (http://alistapart.com/article/application-cache-is-a-douchebag http://alistapart.com/article/application-cache-is-a-doucheb...). I could be missing something, though. EDIT: Forgot to mention that both links come straight from that article.
      - the_duke 10y ago
        Service workers are the way to go now.
        smhg 10y ago
        But they aren't available in Safari. And on mobile, where appcache should be most relevant, Safari can have a significant market share.
        TurningCanadian 10y ago
        They'll come around. And in the meantime, at least Chrome users can benefit.
        kevlened 10y ago
        Until they come around, all iOS users are without service workers, because Chrome on iOS is backed by WKWebView [1]. AFAIK, any custom browser on iOS is required to use WKWebView. [1] http://stackoverflow.com/questions/29895387/service-workers-and-ios http://stackoverflow.com/questions/29895387/service-workers-...
        EGreg 10y ago
        I want Web Push!!
        kinj28 10y ago
        Take a spin at DronaHQ. It allows you to build offline web apps that works cross platform
        digi_owl 10y ago
        iOS Safari has become the IE of mobile?
  - jaimex2 10y ago
    Thanks for the heads up.
sp332 10y ago
Did you know you can use Firefox Developer Tools to remotely debug mobile Chrome? It's still in heavy development, but I'm guessing it's easier than trying to quiesce browser activity and tease out network events manually. https://developer.mozilla.org/en-US/docs/Tools/Valence https://developer.mozilla.org/en-US/docs/Tools/Valence
modeless 10y ago
> Never use the application cache (or service workers) unless you actually need offline features. I disagree. Appcache is deprecated and you should never use it under any circumstances. On the other hand, service workers are cool and there are reasons to use them even if you don't need offline features.
- mschuster91 10y ago
  Safari does not support Service Workers AT ALL, so not using AppCache effectively kills offline support for iOS (source: https://jakearchibald.github.io/isserviceworkerready/ https://jakearchibald.github.io/isserviceworkerready/). Also, according to http://caniuse.com/#feat=serviceworkers http://caniuse.com/#feat=serviceworkers, IE/Edge as well as Safari Desktop and Android 4.x do not support AppCache (compared to near-universal support for AppCache, http://caniuse.com/#feat=offline-apps http://caniuse.com/#feat=offline-apps). This means: use AppCache or lose offline on anything that's not FF/Chrome (on desktops, offline doesn't even matter that much!) or the newest Android. Also, the Service Worker API just plainly sucks when compared with AppCache Manifests. It's a real pity that AC is going down the drain.
  - mbrock 10y ago
    The Service Worker API is very general so it's like a one time cost of implementing something like the AC manifest using the API.
    - chj 10y ago
      This, and IndexedDB API are ugly. Any recommendations on wrapper libraries?
      - mbrock 10y ago
        I've been happy with localForage to do simple K/V in Service Workers. Don't know about cache wrapping libraries... I know e.g. Webpack has an offline plugin thing that works with either AppCache or SW.
thinkloop 10y ago
Is this considered a bug in appcache (deprecation aside)? Why would it download twice at all?
- mfukar 10y ago
  Yeah I missed this completely as well. Two requests for each resource because of the two iframes ("main" and "fullscreen")? It seems to me there's a huge logical leap between "..we were unknowingly downloading much more content than was necessary" and the next paragraph - probably just my unfamiliarity with webdev.
  - ctaintor 10y ago
    In the image on the article, you'll see that I pointed at a duplicate loading of fullscreen.css. If appcache weren't loading this in parallel, it would only be loaded once (by the fullscreen iframe).
    - mfukar 10y ago
      I noticed the duplicate downloads. After all, they're the entire premise behind the investigation. But why does appcache download already requested assets?
xenadu02 10y ago
Since when is only testing in Chrome an acceptable way to develop web applications? I wish the author had shown us some other browser results. I'm curious if the iframe changes affected Safari, Firefox, or Edge. (Others have noted that app cache is deprecated).
- olegkikin 10y ago
  Since Chrome is, by far, the most popular browser: https://upload.wikimedia.org/wikipedia/commons/5/5a/Browser_usage_share%2C_2009%E2%80%932016%2C_StatCounter.svg https://upload.wikimedia.org/wikipedia/commons/5/5a/Browser_... Chrome also has some of the best dev tools built in.
  - nullc 10y ago
    I wonder how much that is distorted by the aggressive preloading that chrome does and by android (since testing chrome on desktop and mobile is not really the same thing)?
  - masklinn 10y ago
    > Since Chrome is, by far, the most popular browser: 2002 called. You're a terrible person.
    - k__ 10y ago
      You would be right if it weren't for Chromium.
    - sametmax 10y ago
      Is its a point of view only in people that are to young to have lived the debacle of IE6 years ? Or do some senor devs actually think testing in chrome only is ok ? Cause I read it more and more, and I find it very alarming. If this becomes a trend, we are going to live in pain all over again.
      - masklinn 10y ago
power78 10y ago
This article just displays the author's lack of knowledge of the subject matter he is developing with. Something tells me it was written just to get the company's name out there.
- hamandcheese 10y ago
  There's no shame in not being an expert. And isn't getting their name out there the point of a company blog?
  - Cozumel 10y ago
    Not when it demonstrates such technical incompetence.
- dx034 10y ago
  The fact that it's on the front page of HN shows that it seems to be interesting to people. Otherwise it wouldn't be here.
calvin0 10y ago
Did this have any improvement on the conversion rate?
deleted 10y ago
[deleted]

116 points by thijser 10y ago

Well, specifically removing the html5 offline application cache if you don't need offline functionality. That it causes duplicate requests, and apparently more of them in chrome mobile than other browsers, is interesting though.

dalanmiller 10y ago
Agreed ^ this title is a big misleading / clickbaity
- tyingq 10y ago
  Not sure why they went that way either..."Offline Cache Causes Duplicate Asset Downloads" would have caught my attention just fine.
  - disconnected 10y ago
    Not a web technology expert, but apparently the appcache feature is deprecated (https://developer.mozilla.org/en-US/docs/Web/HTML/Using_the_application_cache https://developer.mozilla.org/en-US/docs/Web/HTML/Using_the_...) and this dead horse has already been beaten to... er, death? before (http://alistapart.com/article/application-cache-is-a-douchebag http://alistapart.com/article/application-cache-is-a-doucheb...). I could be missing something, though. EDIT: Forgot to mention that both links come straight from that article.
    - the_duke 10y ago
      Service workers are the way to go now.
      - smhg 10y ago
        But they aren't available in Safari. And on mobile, where appcache should be most relevant, Safari can have a significant market share.
        TurningCanadian 10y ago
        They'll come around. And in the meantime, at least Chrome users can benefit.
        kevlened 10y ago
        Until they come around, all iOS users are without service workers, because Chrome on iOS is backed by WKWebView [1]. AFAIK, any custom browser on iOS is required to use WKWebView. [1] http://stackoverflow.com/questions/29895387/service-workers-and-ios http://stackoverflow.com/questions/29895387/service-workers-...
        EGreg 10y ago
        I want Web Push!!
        kinj28 10y ago
        Take a spin at DronaHQ. It allows you to build offline web apps that works cross platform
        digi_owl 10y ago
        iOS Safari has become the IE of mobile?
- jaimex2 10y ago
  Thanks for the heads up.

sp332 10y ago

Did you know you can use Firefox Developer Tools to remotely debug mobile Chrome? It's still in heavy development, but I'm guessing it's easier than trying to quiesce browser activity and tease out network events manually. https://developer.mozilla.org/en-US/docs/Tools/Valence https://developer.mozilla.org/en-US/docs/Tools/Valence

modeless 10y ago

> Never use the application cache (or service workers) unless you actually need offline features. I disagree. Appcache is deprecated and you should never use it under any circumstances. On the other hand, service workers are cool and there are reasons to use them even if you don't need offline features.

mschuster91 10y ago
Safari does not support Service Workers AT ALL, so not using AppCache effectively kills offline support for iOS (source: https://jakearchibald.github.io/isserviceworkerready/ https://jakearchibald.github.io/isserviceworkerready/). Also, according to http://caniuse.com/#feat=serviceworkers http://caniuse.com/#feat=serviceworkers, IE/Edge as well as Safari Desktop and Android 4.x do not support AppCache (compared to near-universal support for AppCache, http://caniuse.com/#feat=offline-apps http://caniuse.com/#feat=offline-apps). This means: use AppCache or lose offline on anything that's not FF/Chrome (on desktops, offline doesn't even matter that much!) or the newest Android. Also, the Service Worker API just plainly sucks when compared with AppCache Manifests. It's a real pity that AC is going down the drain.
- mbrock 10y ago
  The Service Worker API is very general so it's like a one time cost of implementing something like the AC manifest using the API.
  - chj 10y ago
    This, and IndexedDB API are ugly. Any recommendations on wrapper libraries?
    - mbrock 10y ago
      I've been happy with localForage to do simple K/V in Service Workers. Don't know about cache wrapping libraries... I know e.g. Webpack has an offline plugin thing that works with either AppCache or SW.

thinkloop 10y ago

Is this considered a bug in appcache (deprecation aside)? Why would it download twice at all?

mfukar 10y ago
Yeah I missed this completely as well. Two requests for each resource because of the two iframes ("main" and "fullscreen")? It seems to me there's a huge logical leap between "..we were unknowingly downloading much more content than was necessary" and the next paragraph - probably just my unfamiliarity with webdev.
- ctaintor 10y ago
  In the image on the article, you'll see that I pointed at a duplicate loading of fullscreen.css. If appcache weren't loading this in parallel, it would only be loaded once (by the fullscreen iframe).
  - mfukar 10y ago
    I noticed the duplicate downloads. After all, they're the entire premise behind the investigation. But why does appcache download already requested assets?

xenadu02 10y ago

Since when is only testing in Chrome an acceptable way to develop web applications? I wish the author had shown us some other browser results. I'm curious if the iframe changes affected Safari, Firefox, or Edge. (Others have noted that app cache is deprecated).

olegkikin 10y ago
Since Chrome is, by far, the most popular browser: https://upload.wikimedia.org/wikipedia/commons/5/5a/Browser_usage_share%2C_2009%E2%80%932016%2C_StatCounter.svg https://upload.wikimedia.org/wikipedia/commons/5/5a/Browser_... Chrome also has some of the best dev tools built in.
- nullc 10y ago
  I wonder how much that is distorted by the aggressive preloading that chrome does and by android (since testing chrome on desktop and mobile is not really the same thing)?
- masklinn 10y ago
  > Since Chrome is, by far, the most popular browser: 2002 called. You're a terrible person.
  - k__ 10y ago
    You would be right if it weren't for Chromium.
  - sametmax 10y ago
    Is its a point of view only in people that are to young to have lived the debacle of IE6 years ? Or do some senor devs actually think testing in chrome only is ok ? Cause I read it more and more, and I find it very alarming. If this becomes a trend, we are going to live in pain all over again.
    - masklinn 10y ago

power78 10y ago

This article just displays the author's lack of knowledge of the subject matter he is developing with. Something tells me it was written just to get the company's name out there.

hamandcheese 10y ago
There's no shame in not being an expert. And isn't getting their name out there the point of a company blog?
- Cozumel 10y ago
  Not when it demonstrates such technical incompetence.
dx034 10y ago
The fact that it's on the front page of HN shows that it seems to be interesting to people. Otherwise it wouldn't be here.

calvin0 10y ago

Did this have any improvement on the conversion rate?

deleted 10y ago

[deleted]