SPDY Brings Responsive and Scalable Transport to Firefox 11

http://hacks.mozilla.org/2012/02/spdy-brings-responsive-and-scalable-transport-to-firefox-11/

by twapi • 14 years ago

91 43 14 years ago

hacks.mozilla.org

ecaron• 14 years ago

This is terrific news. Now if only Apache would start bundling spdy with their new releases, instead of expecting admins to hunt down the right mod (http://code.google.com/p/mod-spdy/) and hopefully remember to always keep both up to date.

At least nginx is going to start including it: https://twitter.com/#!/nginxorg/status/150112670966747137

newman314• 14 years ago

That's fantastic news re nginx! The last I heard was that they were evaluating it and it's good that they are now committing to deliver support for SPDY.

NelsonMinar• 14 years ago

Is Apache mod-spdy useful yet? The project page says "still an early beta and is not yet suitable for production environments" and everything I've read elsewhere says it's not ready. But things have a way of moving fast, is that outdated info?

mcpherrinm2• 14 years ago

My understanding from when I was working with the Mozilla networking team was that it wasn't very good at all.

I think we used node-spdy to run unit tests, as it was one of the more complete implementations.

AshleysBrain• 14 years ago

Awesome, sounds like good news for the web all-round!

Any news on if other browser vendors (Microsoft, Apple...) are on board?

ck23• 14 years ago

SPDY is great and looking foward to support all around, but looking at that waterfall example, why the heck would anyone develop a website that loads that many elements all at once?

No-one has a viewport that large. You can do lazy image loading in just a few lines of javascript, without jquery. Scripts can be deferred, etc.

I fear SPDY is going to be yet another way to allow shoddy, lazy website functionality.

lukesandberg• 14 years ago

It may be not difficult to do lazy image loading in javascript but ideally you wouldn't have to do it at all. It doesn't encourage lazy or shoddy work. it just allows web developers to focus on creating value rather than just figuring out how to efficiently load images. It's kind of like the argument that garbage collectors are bad because encourage people to use memory inefficient designs, when in fact the reason that garbage collectors are good is because it allows you to focus on more important problems (like design and features). Sure every tool has a different way to shoot yourself in the foot but that doesn't mean you shouldn't use the tool.

tl;dr If SPDY lets me write a website without worrying about how many elements are loading at a time then ill have more time to spend on actually building a product.

munificent• 14 years ago

> why the heck would anyone develop a website that loads that many elements all at once?

I just opened my G+ page and count 50+ user thumbnails. Many modern social websites have lots and lots of small unique user-specific images.

justincormack• 14 years ago

You could sprite a users most common friends to improve this.

dpark• 14 years ago

You can do a lot of things, but why not just speed up the base functionality? Lazy-loading of images speeds up the experience over HTTP, and it will also speed up SPDY. There's only so much optimization you can do at the highest level. At some point, you need the lower levels to just go faster.

0xABADC0DA• 14 years ago

Spdy is not great.

For instance header compression using a shared prefix dictionary saves only a handful (~100 bytes) over TLS compression -- worthless, not to mention it's already had several versions of the prefix dictionary.

Spdy developers didn't even test against HTTP tunneling, which in practice as seen in current Firefox and Opera works just as well. The 'head of line blocking' is not a big deal in practice.

ck23• 14 years ago

Can you link me to what you mean by HTTP tunneling - assuming you do not mean pipelining.

"Tunneling" to me sounds somewhat like proxying but I think you mean something else?

bradgessler• 14 years ago

  You can do lazy image loading in just a few lines of javascript, without jquery. Scripts can be deferred, etc.

Those are hacks. I'd rather have a browser that loads stuff really fast and not have to jump through hoops like spriting, etc. If you're really concerned about deferring the loading of images, that could also be a feature of the browser.

Also, consider that asking the question, "why the heck would anyone develop a website that loads that many elements all at once," is like asking, "why the heck would anybody develop a program that doesn't fit on a 1.44MB floppy?".

ck23• 14 years ago

Why are you loading every single asset on a page that cannot be seen entirely on the screen? Or for a few scrolls?

Why are you loading asssets for the footer when only above the fold is seen on initial page load?

In your floppy comparison, that would be like copying over an entire 16GB SD card just to view a few pictures you took this morning.

masterleep• 14 years ago

SPDY doesn't provide a way to proxy-cache public assets, so it's bad for places that use such caching to mitigate low bandwidth / high latency connections.

magicalist• 14 years ago

which is to be expected with a TLS connection. OTOH you get to drop all the extra TCP handshakes, you get better congestion control, you get header compression, and that encrypted connection is often a really good thing.

http://bitsup.blogspot.com/2011/09/spdy-what-i-like-about-yo...

But yes, there remains no silver bullet, and you'll have to pick the right tool for the job.

eggnet2• 14 years ago

Forcing the use of TLS for SPDY seems to have been intentionally crippling.

yusufg• 14 years ago

Wouldn't this be solved by sending a Cache-Control: public, max-age=<long-duration-in-seconds> header so that the assets can be stored in ISP proxy caches as well as browsers on-disk caches

mcpherrinm2• 14 years ago

The problem is that ISP caches are essentially impossible with SPDY, because of mandatory TLS.

wmf3• 14 years ago

It looks like SPDY will/could support proxies: http://www.chromium.org/spdy/spdy-proxy http://dev.chromium.org/spdy/spdy-proxy-examples

silentOpen5• 14 years ago

SPDY may be technically sound but...

Mozilla Corp: Wholly 0wned Subsidiary of Google Inc

eliben2• 14 years ago

Why? AFAICS, SPDY is open and available for everyone who wants to implement it.

What's so bad about companies making it open, free and open source, thus contributing to a better Internet experience for everyone? No one limited SPDY to Google sites - Microsoft and Yahoo are free to implement it for their servers and enjoy browsing speedups with Chrome and (soon) Firefox 11.

silentOpen5• 14 years ago

So will my web server handle HTTP 1.1, SPDY, and HTTP Next then?

Is Mozilla acting in the interest of the Open Web or was this a bargaining chip with their $300M default search provider deal?

wmf3• 14 years ago

Mozilla refused to implement NaCl and WebP; it looks like they're evaluating Chrome features on a case-by-case basis.

silentOpen5• 14 years ago

Perhaps it does look like that. It also looks like Mozilla has a healthy incentive to shadow Google in the form of their recent search deal.

Is Mozilla doing the best thing for the Web or further cementing the current browser landscape? Will it be better when I have to write my crawlers to work with HTTP 1.1, SPDY, and HTTP Next?

afhof• 14 years ago

Perhaps someone with more experience with network protocols can explain the hype about SPDY, since I cannot seem to figure it out. Looking at the features Google is toting, I can't help but feel underwhelmed:

- Single Request per Connection. It seems that HTTP 1.1 already addressed this with pipelining.

- FIFO Queuing. I feel like the client is in a better position to know in what order the page needs to be rendered than the server. Why shouldn't the server respond in the order that the client asked for?

- Client Initiated Request. Wouldn't it be better inform the client of what it needs rather than just guessing that the client needs these files and sending them down the pipe? It seems that this feature might waste bandwidth, when it could have hit the cache.

- Uncompressed headers. For slow lines, compressed header might be nice if they were very large. That said, I think a better solution to compressing data is to not send it at all. (If you want to increase speed, do you REALLY need to send the User-Agent and Referer at all?) The smallest data is the one that isn't sent.

- Optional data compression. SPDY is forcing data compression? That seems wasteful of power, esp. for mobile devices when sending picture, sound, or video data.

Of course, this list is all just blowing smoke until its actually tested. However, I couldn't find an independent study of SPDY performance.

codeka• 14 years ago

To address some of your points:

- pipelining is still single-file request-response though. With SPDY, you can send multiple requests at once, and the server responds to them in whatever order it likes.

- The point of removing the FIFO queuing is that the server can start responding with simple files before the more expensive resources are calculated. Usually the HTML itself can take a while to be generated server-side, where as CSS and JS files are usually just served straight off disk.

In a FIFO model, the 200ms the client is waiting for the HTML to be generated is just wasted. You could be using that time to be downloading CSS or JS or images, etc.

- There's two options for server-initiated requests in SDPY. One where the server says "Since you requested this resource, you'll probably also want this, this, and this." (i.e. it sends links to the client with the related resources). Other other option is where it actually says, "Since you request this resources, here's these other resources you might be interested in as well."

In the first case, the client can begin processing those other files (e.g. checking it's local cache or actually making a request for them) before the original resource has completed downloading/parsing. In the second case, it could be that the original resource and the "sub-resource" (e.g. HTML file and attached CSS file) have similar caching rules, so if a client requests one it's likely that it'll request the other anyway.

- SDPY also has options for not including those kinds of things (e.g. User-Agent, Host, Accept-*) on every request. But even when you do that, compression still has benefits. Even once you've removed all the redundant data, compression will still help, so why wouldn't you?

- I agree there's certain kinds of content which don't benefit greatly from compression. But on almost all platforms, CPU power is much higher than network capacity. In fact, I can't think of a single platform where that's not the case...

FooBarWidget3• 14 years ago

Http pipelining is quite different. When the server takes a long time to respond to a single request, it stalls the entire pipeline. To efficiently use parallelism you have to start multiple http tcp connections, but that is less efficient than a single connection because they all have to slow start.

As for header compression, have you checked how large headers are these days? They can easily be 1.5 kb.

afimrishi• 14 years ago

- Pipelining would be pretty cool if it worked. There are a number of problems with it: * head of line blocking * transparent proxies that don't support pipelining properly * error detection - FIFO queuing: Why is the client in a better position to know in what order the page needs to be rendered than the server? Isn't the server the one that knows all the resources that need to be sent to the client? - Client initiated request: Yeah, server push is a complicated area. But there are some cases where server push is clearly superior. For example, data URI inlining ruins cacheability. It's better to server push an already cached resource that can be RST_STREAM'd than inline a resource and make it larger and uncacheable. - While we'd like to get rid of headers as much as possible, it's still impractical to completely eliminate headers like User-Agent. - SPDY does not force data compression, and optional data compression has been removed in draft spec 3.

aualin• 14 years ago

Ah, now we are closer to mongrel2 coming with spdy

SPDY Brings Responsive and Scalable Transport to Firefox 11

Related Stories