Linked by Thom Holwerda on Sat 28th Jun 2008 22:09 UTC, submitted by diegocg
"Maybe I'm just naive, but designing a graphics API such that all image data had to be sent over a socket to another process every time the image needed to be drawn seems like complete idiocy. Unfortunately, that is precisely what the X Window System forces a program to do, and exactly what Cairo does when drawing images in Linux - a full copy of the image data, send to another process, no less, every time it is drawn. One would think there would be some room for improvement. Unsurprisingly, others felt the same way about X, and decided to write an extension, Xlib Shm or XShm for short, that allows images to placed in a shared memory segment from which the X server reads which allows the program to avoid the memory copy. GTK already makes use of the XShm extension, and it seems like a good idea to see if Gecko couldn't do the same."
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Member since:2005-11-11
That's how things should work on a sane local graphic setup, but X is far from being "sane". Yes, X.org IS efficient and comparable to other systems, but only because people have spent a lot of time workarounding the stupid things it does so that at the end in local systems it works like other sane systems.
How is any of this "stupid"? Isn't that exactly how most software is supposed to be engineered? What do you expect from them? That shared memory somehow magically works over the network? What kind of answer would satisfy you?
That's the funny thing: X is supposed to be "network transparent", but then the server and the client need to DETECT if they're in "local mode", or if such extension is enabled or not, and make SPECIAL MODIFICATIONS to the code paths so that it works right.
No they don't. "Transparent" means that you don't *have* to do that. Even if you don't use the special modifications, things will still work. It's just that if you do use the special modifications, then things will be more efficient.
Really, what more do you want? It seems that no matter what solution is given, you will never be satisfied until X doesn't work over the network at all. While that may be less "stupid" in your eyes, it'll actually be a step backwards, because then all your apps are still working on the same speed, *and* they don't work on the network anymore.
Member since:2005-07-08
Member since:2005-07-06
Note that sharing the image between the client and the server is not always the right thing to do as setting up shared memory is costly.
So the wise thing to do is to copy small images and use shared memory only for big one.
As for you're rant against X, I'd say that 'standard X' is network transparent, but when you want to use local optimisations, then it isn't network transparent anymore, which makes sense.
That's why we have toolkits which hide this.
Member since:2007-08-12
There's an additional big problem with sockets: Once you send the image to the server, the client can't "share" it, because it's living in the server's address space. So you have a copy of the image on the server AND exactly the same copy of the image on the client. The image is effectively using 2x its size in the memory. The "right fix" for this stupid waste of resources is to free() the image on the client. With shared memory, you can SHARE the image's memory between the client and the process.
The client can't share it? Wtf? Once you send it, it's gone? Have you EVER dealt with sockets at all?
It's not a big deal having it in memory twice. That certainly is not a bottleneck for 99% of all X apps out there nowadays.
The "right fix"... OMG...
News
Linked by Thom Holwerda on 05/25/13 0:45 UTC
"So in summary... Google has pulled the plug on support on a protocol they've helped popularize, after years of promising interoperability, for reasons that are dubious at best, and in a way that leaves people who don't jump to the new Hangouts app unable to talk to their contacts without any feedback that their IMs aren't getting through... And they've done that with no warning to anyone. I imagine there's a bunch of people out there wondering where some of their buddies have gone, or why their messages aren't getting responses, because this isn't documented anywhere." Google really messed this up. Such a dick move.
Linked by Thom Holwerda on 05/24/13 23:59 UTC
The Tizen Greek Community has some screenshots of a very recent build of Tizen running on a Samsung GT-i8800. It looks wholly unremarkable.
Linked by Thom Holwerda on 05/24/13 22:33 UTC
Joint statement to The Next Web from Microsoft and Google: "Microsoft and YouTube are working together to update the new YouTube for Windows Phone app to enable compliance with YouTube's API terms of service, including enabling ads, in the coming weeks. Microsoft will replace the existing YouTube app in Windows Phone Store with the previous version during this time." Good to know these children stopped acting like little pricks. Can we have full Google support in Windows 8 now, please?
Linked by Howard Fosdick on 05/24/13 21:41 UTC
Yahoo is acquiring Tumblr, the microblogging and social networking website, for $1.1 billion USD. Tumblr offers little revenue but lots of eyeballs if Yahoo can monetarize them. Now Yahoo is bidding for Hulu, the streaming video service. After years of ineffective responses while Google, Facebook, and others took large chunks of the online advertising market, Yahoo is fighting back. Can Yahoo reignite the momentum it had at the turn of the century? What do you think?
Linked by Thom Holwerda on 05/24/13 14:44 UTC
"Sources have described iOS 7 as 'black, white, and flat all over'. This refers to the dropping of heavy textures and the addition of several new black and white user interface elements." I couldn't be happier.
Linked by Thom Holwerda on 05/23/13 23:22 UTC
"Ilja van Sprundel, a security researcher with IOActive, has discovered a large number of issues in the way various X client libraries handle the responses they receive from servers, and has worked with X.Org's security team to analyze, confirm, and fix these issues."
Linked by Thom Holwerda on 05/23/13 22:04 UTC
"Google is facing a new antitrust probe by the U.S. Federal Trade Commission into whether the company is using its leadership in the online display-advertising market to illegally curb competition, people familiar with the matter said." Sucks to be Google today, apparently.
Linked by Thom Holwerda on 05/23/13 22:01 UTC
"In the midst of the major press blitz surrounding its annual I/O Conference, Google dropped some unfortunate news about its instant messaging plans. In several places around the web, the company is replacing the existing 'Talk' platform with a new one called 'Hangouts' that sharply diminishes support for the open messaging protocol known as XMPP (or sometimes informally Jabber), and also removes the option to disable the archiving of all chat communications. These changes represent a switch from open protocols to proprietary ones, and a clear step backward for many users." That's why I always say: only suckers trust companies.
Linked by Thom Holwerda on 05/23/13 17:52 UTC
"The wave of departures is a sign of internal struggle, but amidst all the bad news, there is a glimmer of hope. According to an anonymous HTC executive cited by WSJ, the crucial HTC One is selling 'pretty good so far'. The executive revealed that HTC sold about five million One units since launch, a performance that is deemed encouraging. However, sales have been limited by the persisting supply issues that still plague the production of the HTC One." Finally some good news for HTC. Five million units amidst supply constraints is very impressive.
Linked by Thom Holwerda on 05/22/13 22:23 UTC
"Sony gave the PS4 50% more raw shader performance, plain and simple (768 SPs @ 800MHz vs. 1152 SPs & 800MHz). Unlike last generation, you don't need to be some sort of Jedi to extract the PS4's potential here. The Xbox One and PS4 architectures are quite similar, Sony just has more hardware under the hood. Weâll have to wait and see how this hardware delta gets exposed in games over time, but the gap is definitely there. The funny thing about game consoles is that itâs usually the lowest common denominator that determines the bulk of the experience across all platforms. On the plus side, the Xbox One should enjoy better power/thermal characteristics compared to the PlayStation 4. Even compared to the Xbox 360 we should see improvement in many use cases thanks to modern power management techniques." AnandTech does its usual in-depth thing.More News »
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Member since:
2005-07-08
There's an additional big problem with sockets: Once you send the image to the server, the client can't "share" it, because it's living in the server's address space. So you have a copy of the image on the server AND exactly the same copy of the image on the client. The image is effectively using 2x its size in the memory.
The "right fix" for this stupid waste of resources is to free() the image on the client. With shared memory, you can SHARE the image's memory between the client and the process.
That's how things should work on a sane local graphic setup, but X is far from being "sane". Yes, X.org IS efficient and comparable to other systems, but only because people have spent a lot of time workarounding the stupid things it does so that at the end in local systems it works like other sane systems.
That's the funny thing: X is supposed to be "network transparent", but then the server and the client need to DETECT if they're in "local mode", or if such extension is enabled or not, and make SPECIAL MODIFICATIONS to the code paths so that it works right. There's no "transparency" anymore, as applications (toolkits) need to be aware of such low-level graphic details and code different paths according to the results. It has been needed to create many X extensions, it has been needed to MODIFY applications to use those extensions...oh my god, it's just not fun even to think about it. And to think that backwards compatibility is all that was stopping people from doing it right...
Edited 2008-06-29 09:20 UTC