The 64 Milliseconds Manifesto

https://apitman.com/13/#64-ms

by apitman • 7 years ago

65 107 7 years ago

apitman.com

stephen82• 7 years ago

...and on my browser [Firefox ESR 60.8.0esr (64-bit)] it takes 241ms to load this plain HTML website.

mempko• 7 years ago

clearly, browsers fail. have you tried lynx?

noir_lord• 7 years ago

Markup is invalid as well.

I thought it was a presentation or something and I needed to use arrows to navigate it..turns out.

Well not really sure what the point of the thing is tbh.

joe_hoyle• 7 years ago

This website isn't an interactive software application though!

kzrdude2• 7 years ago

It's loading favicon.ico, which redirects to favicon.ico/ which returns some kind of html page (larger than the / page itself!), so that seems misconfigured.

stefan_• 7 years ago

You also see the background flash as it "renders". The whole website concept is just rotten and dead if you want to even get close to as smooth as Doom in 1995 on computers with less computing power than a shader processor in my mobile phone. Cue the discussion on "speed of light" in this thread while people applaud getting your website to display in under a second.

dahart11• 7 years ago

How long does it take Firefox to show you a loading spinner & new tab?

smadge• 7 years ago

PageSpeed Insights says it is .2 seconds time to interactive on desktop and .8 on mobile.

kzrdude2• 7 years ago

For reference that's about this much:

16 ms → 62 Hz

32 ms → 31 Hz

64 ms → 16 Hz.

mattmar96• 7 years ago

Meh.. sure. Any reason behind these specific figures?

apetresc• 7 years ago

They're powers of 2, so clearly they are significant for deep technical reasons.

theandrewbailey• 7 years ago

16.666...ms (aka 16ms) is 1 complete cycle at 60Hz, the frequency most computer displays operate at. 32ms and 64ms are approximately 2 and 4 cycles respectively.

ksec• 7 years ago

In an interactive software application, any user action SHOULD result in a noticeable change within 16ms

In many cases the Input Lag ( Especially Touch Screen ) in itself is more than 16ms. That is excluding the processing from CPU to GPU rendering and your Display Lag.

mrob3• 7 years ago

Apple IIe managed 30ms total[0]. There's no reason why modern computers, which are thousands of times faster, shouldn't manage 16ms. The slow response of modern systems is the result of a deliberate choice to prioritize ease of development over user experience. We can do better.

[0] https://danluu.com/input-lag/

viklove• 7 years ago

You speak as if ease-of-development doesn't enhance UX. Of course it does. If a team can ship features and fix bugs faster, the UX does improve. Most would say that's worth it over shaving 15ms off the input lag.

nemothekid2• 7 years ago

The mechanism that gave the Apple IIe such low latency has little to do with processing power - the keyboard had an exotic setup that you likely won't get over something as generic USB.

wait-a-minute• 7 years ago

This manifesto's website takes longer than 64 milliseconds to respond though.

ar_lan• 7 years ago

I enjoy that it gives no rationales. Without reasons/research/sources, these are just arbitrary numbers.

novok• 7 years ago

As nice as this goal is, I think the RAIL model's benchmarks are a bit more realistic:

https://developers.google.com/web/fundamentals/performance/r...

earthboundkid• 7 years ago

Too vague, not actionable, no context.

More useful:

People can often respond to things within a few frames (1/60 second = 16ms). For some interactions, it's useful to respond within one frame. For others, more latency is acceptable. For yet others, sub-frame latency is required (e.g. VR/AR). Light can move ~3,000 miles in that time, which is a hard limit on latency.

yummypaint2• 7 years ago

Meanwhile major news sites take 45 seconds to load content randomly accross the page so the text jumps around and is unreadable.

adrianmonk• 7 years ago

I kind of want web browsers to give a budget of layout changes. Once a page does enough things to exceed the budget, too bad, your layout is stuck there.

If the user does something interactive to warrant further layout changes, then you're allowed to start changing things again.

The idea is to make it cost something to change the layout. Then people will have to actually try not to do it excessively.

yummypaint2• 7 years ago

On many sites the layout isnt even relevant, and all people actually want is to read the plaintext and locate any relevant images amongst the chaos. Im wondering about a browser extension or something that extracts this information directly and re-renders it in simple (like year 2000 era) html. I would kill for this on my phone.

kissgyorgy• 7 years ago

I really like this, even though if it is impossible with today's microservice architectures...

A couple of years ago I was thinking about this either and someone suggested a study defined 0.1, 1 and 10 seconds as limits: https://stackoverflow.com/questions/17138585/what-is-the-max...

feifan• 7 years ago

The interface isn't necessarily related to backend services (i.e. you don't need backend services to drive every change in the interface)

juancn• 7 years ago

It's impossible. Lightspeed doesn't allow for that on websites if you're far enough from the servers.

If you add intermediate network gear, it's hard enough to get across half the globe in under 180ms (I'know, I live in Argentina and that's my ping time to almost anywhere non local).

You could fake it somehow in some scenarios or with an awful lot of money.

mrob3• 7 years ago

Speculatively make and cache likely requests. Predict server responses client-side, and update with the server response if it differs. Multiplayer games have been hiding latency since QuakeWorld.

littlestymaar5• 7 years ago

Have you ever tried playing a competitive game with above 300ms ping?

Dylan168078• 7 years ago

In most situations you can have more than one server. If you focus on the 64ms goal, and you budget 20 for ethernet/fiber, that gets you 2000km each way to reach the closest one.

youareostriches• 7 years ago

Lightspeed doesn't allow for that on websites if you're far enough from the servers.

This is a hint that you're writing for the wrong platform. Write real apps.

acdha2• 7 years ago

It's impossible. Lightspeed doesn't allow for that on websites if you're far enough from the servers.

Your second sentence explains why the first is wrong. Yes, you can’t have the entire world using a single server but it’s never been easier to get servers around the world and the new edge compute services are further improving that.

littlestymaar5• 7 years ago

around the world

Only if your «world» means «developed countries only»…

ChristianBundy• 7 years ago

Lightspeed doesn't allow for that on websites if you're far enough from the servers.

This assumes that we need remote servers to do our computing for us. :~) P2P software doesn't require remote servers, plus it means your apps still work offline.

dahart11• 7 years ago

This manifesto is made just for you! Waiting for the response before updating the screen is the wrong answer. It’s not impossible, you’re assuming incorrectly that the manifesto is saying the final result needs to be on screen. It didn’t say that, it said the app needs to respond to action visually, not that the response or interaction sequence must be completed within that time frame.

The right answer for web and networked applications is to update the screen with UI that acknowledges the user action and shows the user that the result is pending. Ideally, progress is visible, but that’s tangential to the point of the manifesto.

A client can, in fact, almost always respond to actions within these time constraints. The point is to do something, rather than wait for the network response.

fishnchips• 7 years ago

In some cases (most requests succeed, and you know the likely outcome) an optimistic update would suffice.

PeterisP2• 7 years ago

Getting a CDN to put your content much closer to users does not require an awful lot of money. The vast majority of your users shouldn't be across half the globe; if you're a tiny local shop, then you're targeting local users; and if you're targeting multiple continents then it's not that hard to host stuff on multiple continents cheaply even if you're just a couple people, there are services available for that.

Dylan168078• 7 years ago

If I'm going to have a full screen of content after 64ms, why do I care about having something incomplete but 'actionable' after 32ms? And the policy of showing some feedback before then is useful in some circumstances but not very important in others.

The 64ms goal by itself is clearer and more useful than this combo of three goals.

spullara• 7 years ago

It takes 250ms to curl this website. Ping time to the site is less than 64ms though and it is cached by Cloudflare and still can't seem to serve it that fast. Maybe HTTPS can't get under 250ms or so? Only way for me to get under 250ms is to use HTTP...

toast0• 7 years ago

Depending on how your environment is configured...

Curl will do one round trip to your resolv.conf configured resolver

Then you have one round trip for tcp.

Then another for TLS hello (presuming TLS 1.3 or false-start)

Then one last round trip for HTTP.

Assuming cached DNS, you need a ping to the server of about 21ms to get content via https in 64ms. And that's assuming you can get enough content for a screens worth in the initial congestion window (10ish packets, so let's say 15kb). Good luck!

Oh, and my DSL connection adds at least 20ms to the path, and that's not unusual.

PeterisP2• 7 years ago

HTTPS requires a bunch of redundant roundtrips. We need adoption of QUIC/HTTP3 to reduce that.

sarah180• 7 years ago

Is this an example of the kind of reactive, interactive design you're advocating? I don't see how this is helpful: it's dogmatic and doesn't address the actual tradeoffs that might be at play. Why 64 ms? And 32 and 16? What studies are you relying on to suggest that 65 ms is too slow or that 30 ms is too slow for initial feedback? How does it affect user behavior? What is advised when these rules, especially the "full screen of content" cannot be met because of things like external dependencies out of the site's control?

loup-vaillant4• 7 years ago

60 frames per second.

- 16ms: one frame

- 32ms: two frames

- 64ms: four frames

So it's really 1, 2, 4. Maybe we could have 1, 2, 3, but I'm guessing the "48ms Manifesto" wouldn't sound too great: they probably preferred to have a nice power of two.

And if I may, I think the manifesto is basically right. Something I have to wait several frames for before it reacts feels sluggish. When I type a character, I want it now, not 5 frames later. When I move the mouse, I want it in sync, not lagging behind my hand. Touch screens are even more exacting. They only feel perfect when latency falls under one millisecond. But that last one isn't achievable in practice on current stock hardware…

userulluipeste• 7 years ago

Well then... why 60 frames per second? This isn't obvious to me and I presume to others using today's tech too.

dahart11• 7 years ago

Yeah it's simplistic and doesn't explain the rationale, but having studied human perception a bit, I know without further explanation that this is targeting the time frames of our human ability to see change. The numbers here are similar to the reasons most movies are 24fps.

What is advised when these rules, especially the "full screen of content" cannot be met because of things like external dependencies out of the site's control?

This is missing the point, and many people here seem to be attempting to pick the same nit. You never have to wait for external dependencies to show changes on screen. This is how browsers and well designed high traffic websites like YouTube already operate. When you take action, you are shown UI changes on-screen that indicate the action is in progress. The manifesto is saying to acknowledge the user action so the user knows the application received the request. It is not saying everything in the world needs to be done in 64ms. Applications can always acknowledge the request immediately, and yet some still don't.

tedunangst2• 7 years ago

How can I show one full screen of content when it takes longer than 64ms for the content to get from there to here? An acknowledgment that the content is coming is not a screenful of content.

jlg233• 7 years ago

It is not saying everything in the world needs to be done in 64ms.

Well, most actually could be. And a snappy "acknowledgement" only impresses me the first time. The second time I stare at the loading indicators in disbelief, while waiting for the not-so-snappy action to execute.

noobermin• 7 years ago

I don't agree with the page too, it seems better to make terms on order of magnitude may be (10s of ms, 100s of ms), but in their favor the exact times might not be hard limits but maxima in terms of latency, with the hope that you can be better. A point against me is specific numbers (ones that are essentially memorized by every programmer as powers of two) are easy to remember and good for messaging purposes.

wbhart• 7 years ago

They missed the remaining portion of the manifesto:

* Websites making controversial claims should state clearly the claim in the first paragraph

* Controversial claims should be backed up by at least a summary of a well reasoned argument within the first 5 paragraphs.

* Controversial claims should be backed up by citing sources.

loup-vaillant4• 7 years ago

Controversial? Really? What's written there is basically what's required for interactive speed. What's described here is basically what's required for interaction to feel instantaneous. Why should we settle for anything but immediacy?

Sure, with all those laggy applications we have right now, we tend to become desensitised. That's not an excuse, though.

Also note that in some cases, we're not even close to acceptable latency. Finger tracking on touch screens for instance, require a one millisecond response time to feel perfect. Otherwise the objects we drag will lag behind our fingers.

greencore• 7 years ago

People must learn some patience instead of wasting our time and talent on optimizing stuff for those milliseconds.

AnIdiotOnTheNet• 7 years ago

Ah yes, ye olde "my time as a developer is worth more than that of mere users". That kind of thinking is the reason modern computing sucks so bad.

dangus6• 7 years ago

The most popular website in the world, known for incredible speed, google.com, took me 197 ms to load, with 139ms spent waiting.

A search for "hacker news" took 186 ms, with 111 ms spent waiting.

64.ms itself takes 3 ms for DNS lookup, 39 ms for the initial connection, and 29 ms for the SSL - total of 71 ms before any content download happens.

I'm on 802.11 AC WiFi seated about 5 feet from my router.

Apparently, users are quite willing to wait longer than 64 milliseconds.

I'm no web developer, so I don't claim to have expertise, but it really does seem like an unreasonable expectation. As soon as you have any sort of complex functionality the idea falls apart:

"Wait for the credit card payment to process"

"Download a high resolution image" (that counts as a page of content right?)

"Start watching this 4K video"

"Download a CSV of your 100,000 row data set"

dahart11• 7 years ago

There are about 20 different things that happen on screen while google.com is loading in my Chrome browser, starting within 16ms.

dangus6• 7 years ago

But when can I interact with it?

To be honest, I have no way of knowing or testing, because ~180 ms is already faster than I can see or react to.

64.ms itself takes 3 ms for DNS lookup, 39 ms for the initial connection, and 29 ms for the SSL - total of 71 ms before any content download happens.

Then my browser waits for 250ms (slower than Google).

loup-vaillant4• 7 years ago

There are other things than the web. Though maybe not for long, if everyone starts thinking like you just did…

dangus6• 7 years ago

It just shows you how silly and arbitrary the manifesto is. Any "interactive software application" should show "at least a full screen of content."

My web browser is an interactive software application and it doesn't even start up and put an about:blank page on my screen in 64 ms. Repeat this statement for literally any GUI application, the containing window don't even appear in 64 ms.

And anyway, how big is a "screen?" What is the measurement of a screen of content? Do I have to fill up a 320x480 screen or a 3840x2160 screen? How many characters is a "screen? Pictures? Video frames?"

If you make some kind of transform in Illustrator or Photoshop, why would it be reasonable to give up the quality of the end result just to hit that arbitrary 64 ms goal? Can Illustrator even load/render a simple design like a company logo in 64 ms? A lot of interactive software combines batch processes with live interaction, too, so why would it be reasonable to be unwilling to wait more than 64ms for calculation, rendering, or transformation procedures? Of what use would the unfinished content be if it were shown to me within 64ms?

Essentially no application follows this guideline and never will.

This website is more of an exercise in snark and elitism than anything else.

juped• 7 years ago

Google hasn't had incredible speed for many years, now. That reputation is woefully out of date.

kevin_thibedeau2• 7 years ago

Will you wait > 100ms for a checkbox to change state? The point is that actions that should be instantaneous need to appear as such within the limits of human perception. Complex operations can take longer.

dangus6• 7 years ago

No, but that's not what the manifesto says.

Full screen of content within 64 ms.

Sure, I definitely expect a checkbox to do something in < 100ms. Show that its state changed and at the very least show me some kind of loading icon so I know something is happening.

But a full screen of content in 64 ms? Unreasonable, and really a completely undefined unit of measure (what is/how big is a "screen" and how much content can fit within? How do you measure audio or video content? What happens when I'm working with vector graphics that can't possibly render in 64 ms?)

calibas• 7 years ago

Note that it says "interactive software application" not "website", though it's possible on a website using a single page application and preloaded resources. Any time you're fetching a resource from some external source, it's unreasonable to expect it to load in under 64ms.

I assume the intention isn't speed alone, but part of the user experience. When you interact with an application, you should be able to tell immediately that it's recognized your input and something is happening.

CSSer2• 7 years ago

I think your examples hinted at an important part of network-driven applications: loading. Loading statuses, done correctly, and with the right attention to detail, can result in users waiting more patiently than many would ever believe. Sometimes that’s as small as conveying “something is happening” and other times it requires conveying details that communicate why the user must wait so that they can simply think, “that seems reasonable. I understand why that could take some time”.

lgats• 7 years ago

Instant.page and Quicklink attempt to speed up the perceived loading of pages by pre-loading pages before a user clicks.

The "Test your click speed" button is fun to play with. Times 50-100 ms for mobile and 150-300 ms for desktop are reasonable long for performing some pre-loading.

[1] https://instant.page/ [2] https://github.com/GoogleChromeLabs/quicklink

korethr2• 7 years ago

By the numbers it sounds like this is built around an assumption of 60fps. The rounding is wrong, but let's roll with it. That's a noticeable change by the next frame, actionable information two frames thereafter, and a full screen worth of content four frames thereafter.

My intuition says that's steep. Noticeable change 1 frame later might be doable with a web app, if the app is structured well and focuses on fast response times. However, I don't think actionable information two frames later, or a full screen of content four frames later is feasible for a network-based application, especially given the fact that just crossing local layer 3 network segments can add 10s of ms to your latency, depending on the router's load.

Really, these numbers strike me as only achievable by an application where all data and processing is done locally on the computer that controls the display. Even then, these target numbers still feel steep.

ekimekim• 7 years ago

In a networked app where your latency is too high for these figures, or if you need to do some large number crunching etc, you should instead focus on giving the user feedback that progress is occurring. A progress bar, a spinning ball, etc are far better than nothing. Just as long as you acknowledge that the user has requested an action, and give the user confidence the action is proceeding.

korethr2• 7 years ago

That, I don't disagree with at all. There's been more than one time I've clicked on something, and then waited for the computer to do something that lets me know it's received my command and acted on it. It can be damn frustrating.

AndriyKunitsyn• 7 years ago

Too vague. Isn't moving caret in a text field "any user action"? Then why should it invoke a full screen of content?

aidenn0• 7 years ago

I just want at least a filler response within ~150ms when I tap a button on my phone. Occasionally I will miss a touch target. If I haven't seen a response, I will assume I missed the touch target.

devadvance• 7 years ago

It seems as though relying on something a bit more verbose, such as the guidance from Nielsen Norman Group [1], might be more effective in helping people building software.

In particular:

0.1 second is about the limit for having the user feel that the system is reacting instantaneously, meaning that no special feedback is necessary except to display the result.

[1] https://www.nngroup.com/articles/response-times-3-important-...

ghostbust555• 7 years ago

64ms? Without any context or reasoning? Wrong all ui should load in 100ns and anyone who disagrees is an idiot.

arch-ninja• 7 years ago

I love this. Software developers too often focus on the final end state and this distracts from the state changes in the middle of any process.

By focusing on UI responsiveness you vastly improve discoverability and interoperability because it naturally decouples the problem into a model/view/controller design. Best of all you can't mis-design: the responsiveness is your constraint, and if the design doesn't give you responsiveness you KNOW it is a poor design.

This is the ultimate quality litmus test.

ninthcat• 7 years ago

https://webpagetest.org/result/190924_7C_b9373b51a084f69f1bc...

loup-vaillant4• 7 years ago

Half the comments here seem to assume this manifesto is about web sites. Can I remind everyone that many applications run locally?

CSSer2• 7 years ago

They do? The web is the future!

jenkstom• 7 years ago

The fastest I can view and respond to information is maybe 2 times per second if I'm not really viewing anything. So I'd say 512ms makes more sense or maybe 256ms if you want it to "feel" snappier (assuming we are sticking to powers of 2 for some reason). Any higher is looking more for animation speed than usability speed.

dang• 3 years ago

The URL was originally https://64.ms/ but it no longer works, so we've changed to one that does (by the submitter's request).

The 64 Milliseconds Manifesto

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