Re: Doubts about the benefits of WebSockets
FWIW, in my case I fall back to polling every 10s in case websockets are not supported. However, as soon as IE9 penetration drops to an insignificant level I will stop with fallbacks. On Tue, Jul 15, 2014 at 7:11 PM, andr...@itship.ch wrote: Seems like we have a similar goal, Amaury! Cool :) On Mon, Jul 14, 2014 at 03:52:42AM -0700, Amaury Hernández Águila wrote: Yeah that would be nice. So, isn't that a good reason to have websockets in PocoLisp? I would not say so. In a video game you have so much continuous communication going on (most notably the stream of image frames), that you don't need an extra channel. -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe Online games don't work by feeding single frames to clients. There are now a few companies trying to get this alive - like video streaming for games - but this not working fluently as the amount of data to transfer when rendering images on the server is just too big to have a reasonable latency for real-time-games (in opposite to turn based games). The continuous communication in a online game is chat and game logic messages - user input going up to the server, and results of that inputs together with results of behaviour from other agents going down to client
Re: Doubts about the benefits of WebSockets
FWIW, in my case I fall back to polling every 10s in case websockets are not supported. However, as soon as IE9 penetration drops to an insignificant level I will stop with fallbacks. Make a user agent statistic from your users, or try to obtain data about your target audience. Rumour is, like half of Asia is still running on pirated WinXP using old versions of IE (even IE6), so its surely good to have fallbacks around. Of course, this is probably insignificant, but still interesting how stubborn this old stuff sticks around. A point for trying to make software well from the start, you never know how long it will haunt you or others after release... Mobile support of websockets in the current client versions seems to be pretty good: http://caniuse.com/websockets Question is what version the user-base actually is using... --- Just some random sources for my statements, not exactly well researched stuff: http://www.techinasia.com/windows-xp-now-dead-but-200-million-machines-in-china-still-using-it/ http://www.troyhunt.com/2010/08/aye-pirates-be-reason-ie6-just-wont-die.html -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
How reliable are the statistics from w3schools? ( http://www.w3schools.com/browsers/browsers_stats.asp). It is stated in this page http://www.w3schools.com/browsers/browsers_explorer.asp that IE6 users are about 0.1% of the total Internet users. When I first began web development I always tried to make my websites compatible with every browser. But now I'm getting tired of that (particularly, tired of IE) and now I just care about the latest versions of Chrome and FF. At least this is true for personal projects. I understand that clients might require their products to be fully compatible with every browser. 2014-07-15 14:41 GMT-07:00 andr...@itship.ch: FWIW, in my case I fall back to polling every 10s in case websockets are not supported. However, as soon as IE9 penetration drops to an insignificant level I will stop with fallbacks. Make a user agent statistic from your users, or try to obtain data about your target audience. Rumour is, like half of Asia is still running on pirated WinXP using old versions of IE (even IE6), so its surely good to have fallbacks around. Of course, this is probably insignificant, but still interesting how stubborn this old stuff sticks around. A point for trying to make software well from the start, you never know how long it will haunt you or others after release... Mobile support of websockets in the current client versions seems to be pretty good: http://caniuse.com/websockets Question is what version the user-base actually is using... --- Just some random sources for my statements, not exactly well researched stuff: http://www.techinasia.com/windows-xp-now-dead-but-200-million-machines-in-china-still-using-it/ http://www.troyhunt.com/2010/08/aye-pirates-be-reason-ie6-just-wont-die.html -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Doubts about the benefits of WebSockets
Hi Henrik, first of all, thank you for the article and the good work! However, I must say that I have doubts about the benefits of WebSockets in general. I cannot see that they are worth the overhead. They introduce a complicated machinery, which is not just a simple protocol extension, but a fundamental change in the HTTP transaction principles. As that, it violates the PicoLisp philosophy of minimizing the number of concepts. Second, they require a browser which can handle them. This excludes, for example, text browsers like 'w3m'. Third, I'm still waiting for the killer-application which really needs them. All scenarios I have seen so far can be handled with the standard PicoLisp framework much more easily - without explicit maintenance tasks lile clearing out disconnected clients and sending a ping ... to keep the connection alive. All this is already done automatically. To keep with the typical realtime chat, a minimal setup could be: #!/usr/bin/pil (load @lib/http.l @lib/xhtml.l @lib/form.l) (de chat () (app) (action (html 0 Chat @lib.css NIL (form NIL (gui 'log '(+FileField) chat.log 60 20) (--) (gui 'msg '(+TextField) 60) (gui '(+Click +Auto +Button) 2000 'This 2000 Chat '(when (val (: home msg)) (out +chat.log (prinl @)) (clr (: home msg)) ) ) ) ) ) ) (server 8080 !chat) (wait) Put this into a file called chat, set it to executable, and start it as: $ ./chat Then point some browser windows to http://localhost:8080;. Everything typed into the 'msg' text field (and even in the 'log' field above it) appears in all other connected clients after maximally 2 seconds. Note that also text browsers like w3m can be used. Just the automatic firing of the button won't happen without JavaScript, so the user must press the Chat button whenever he wants an update. Also note that due to the same-origin-policy of JavaScrpt (repeatedly discussed here) the Chat buttun must be pressed in the beginning once, unless - as usually recommended - 'httpGate' is running and the client connected directly to http://localhost;. Other features like a notification system can be implemented even simpler. You could, for example, clone the existing 'ping' and 'ping' functions in @lib/xhtml.l and extend them to carry a payload. ♪♫ Alex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
Hi Alex, doesn't all that polling you're doing introduce a lot of unnecessary requests to the server. There can be up to 200 persons logged in at the same time at the site where I'm using websockets now, that would be 100 HTTP POSTS per second with full HTTP headers etc just to check for notifications that perhaps 1 or 2 of them would get per 10 seconds. See figure 3 here: http://www.websocket.org/quantum.html On Mon, Jul 14, 2014 at 2:44 PM, Alexander Burger a...@software-lab.de wrote: Hi Henrik, first of all, thank you for the article and the good work! However, I must say that I have doubts about the benefits of WebSockets in general. I cannot see that they are worth the overhead. They introduce a complicated machinery, which is not just a simple protocol extension, but a fundamental change in the HTTP transaction principles. As that, it violates the PicoLisp philosophy of minimizing the number of concepts. Second, they require a browser which can handle them. This excludes, for example, text browsers like 'w3m'. Third, I'm still waiting for the killer-application which really needs them. All scenarios I have seen so far can be handled with the standard PicoLisp framework much more easily - without explicit maintenance tasks lile clearing out disconnected clients and sending a ping ... to keep the connection alive. All this is already done automatically. To keep with the typical realtime chat, a minimal setup could be: #!/usr/bin/pil (load @lib/http.l @lib/xhtml.l @lib/form.l) (de chat () (app) (action (html 0 Chat @lib.css NIL (form NIL (gui 'log '(+FileField) chat.log 60 20) (--) (gui 'msg '(+TextField) 60) (gui '(+Click +Auto +Button) 2000 'This 2000 Chat '(when (val (: home msg)) (out +chat.log (prinl @)) (clr (: home msg)) ) ) ) ) ) ) (server 8080 !chat) (wait) Put this into a file called chat, set it to executable, and start it as: $ ./chat Then point some browser windows to http://localhost:8080;. Everything typed into the 'msg' text field (and even in the 'log' field above it) appears in all other connected clients after maximally 2 seconds. Note that also text browsers like w3m can be used. Just the automatic firing of the button won't happen without JavaScript, so the user must press the Chat button whenever he wants an update. Also note that due to the same-origin-policy of JavaScrpt (repeatedly discussed here) the Chat buttun must be pressed in the beginning once, unless - as usually recommended - 'httpGate' is running and the client connected directly to http://localhost;. Other features like a notification system can be implemented even simpler. You could, for example, clone the existing 'ping' and 'ping' functions in @lib/xhtml.l and extend them to carry a payload. ♪♫ Alex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
On Mon, Jul 14, 2014 at 11:41:08AM +0200, Alexander Burger wrote: Not such a big problem. If I measure the described chat client, pinging every 2 seconds, I get 335 Bytes per second on the average. This amounts to 65 kB per second for 200 clients. Not a big problem today. Typically Oops, no! It is even less than that. The size I wrote above includes log information like time stamps and process IDs. Without them, there are only 218 Bytes per second, giving 44 KB per second. -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
Hi Tomas, thing like the example from Alex, then the amount of work on the server seems rather small and avoiding sending HTTP headers seems like pointless micro-optimization. True. The posts caused by the +Auto button are POST /55319/29110032894590418~!jsForm?!chat?*Menu=+0*Tab=+1*ID= HTTP/1.1 Host: localhost User-Agent: Mozilla Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Language: en-us,en;q=0.5 Accept-Encoding: gzip, deflate Referer: http://localhost/ Content-Length: 51 Content-Type: text/plain; charset=UTF-8 Connection: keep-alive Pragma: no-cache Cache-Control: no-cache *Gui:-3=Chat*Get=1*Form=2*Evt=0*Gui:1=*Gui:2= with a size of 449 bytes. This is less than the default TCP packet size of 1152 bytes, so a headerless protcoll wouldn't save anything here. What about putting the log field into an iframe with automatic reload instead of the +Auto button which needs javascript? Would that not be even better? I don't know, I have never use iframes. But with them we again introduce a new concept and new dependencies, which I try to avoid. The +Auto button is more general, and I use it quite often. ♪♫ Alex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
How about a browser videogame? Developing videogames in PicoLisp would be great. I think I'll start one tomorrow. El jul 14, 2014 3:21 AM, Alexander Burger a...@software-lab.de escribió: On Mon, Jul 14, 2014 at 12:02:10PM +0200, Alexander Burger wrote: with a size of 449 bytes. This is less than the default TCP packet size of 1152 bytes, so a headerless protcoll wouldn't save anything here. Sorry, forget that! I think there is no default TCP packet size :) Anyway, we are not talking about huge amounts of data here. ♪♫ Alex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
Yeah that would be nice. So, isn't that a good reason to have websockets in PocoLisp? El jul 14, 2014 3:49 AM, Alexander Burger a...@software-lab.de escribió: Hi Amaury, On Mon, Jul 14, 2014 at 03:26:15AM -0700, Amaury Hernández Águila wrote: How about a browser videogame? Developing videogames in PicoLisp would be great. I think I'll start one tomorrow. Really? That would be great! I suspect there are many people here interested to help. ♪♫ Alex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
On Mon, Jul 14, 2014 at 03:52:42AM -0700, Amaury Hernández Águila wrote: Yeah that would be nice. So, isn't that a good reason to have websockets in PocoLisp? I would not say so. In a video game you have so much continuous communication going on (most notably the stream of image frames), that you don't need an extra channel. -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
44KB / second is far from insignificant IMO, it works out to 0.35 Mbit/s if I'm not mistaken, we're paying 20 EUR per month per 1Mbit at our current co-location. Well worth spending a couple of days to avoid permanently. Plus, the goal is to have much much more people logged in in the future. On Mon, Jul 14, 2014 at 4:52 PM, Alexander Burger a...@software-lab.de wrote: On Mon, Jul 14, 2014 at 11:41:08AM +0200, Alexander Burger wrote: Not such a big problem. If I measure the described chat client, pinging every 2 seconds, I get 335 Bytes per second on the average. This amounts to 65 kB per second for 200 clients. Not a big problem today. Typically Oops, no! It is even less than that. The size I wrote above includes log information like time stamps and process IDs. Without them, there are only 218 Bytes per second, giving 44 KB per second. -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
Hi Henrik, 44KB / second is far from insignificant IMO, it works out to 0.35 Mbit/s if I'm not mistaken, we're paying 20 EUR per month per 1Mbit at our current co-location. Well worth spending a couple of days to avoid permanently. wow, 20 EUR per 1Mbit? 160 EUR per 1MByte? In 2014? I can't believe that. My home connection costs 24 EUR a month without trafic restrictions iirc and is much faster than that:-) Cheers, Tomas -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Doubts about the benefits of WebSockets
Yes but that's a residential subscription, before we moved to co-location we used fasthosts.co.uk (highly recommended if you don't do the kind of realtime stuff I do at work). With fasthosts you get unlimited speed and transfers but when you do what we do you quickly realize that it doesn't work good because you have no control over how your boxes are spaced out in the facility. If some other customer is transferring massive amounts of data between one of their boxes the quality of your LAN connection could start suffering. At one point another customer of theirs got attacked by some kind of denial of service attack which affected us too since it's all shared. In the co-lo where we are now we rent space, a whole rack actually, so our machines are next to each other served by our own switches. This has resulted in zero network related outages as opposed to the situation at fasthosts. To the co-location facility there are 3 geographically separated uplinks which we buy dedicated space on, ie we have unlimited amount of transfer per month of course but we have a roof on how much we can transfer per second (up and down), this roof can be raised by 20 EUR per Mbit/s per month. We don't share this with anyone else so the speed is 100% guaranteed, if we don't utilize it that space is not used, the actions of other customers in the co-location facility can't affect us as they are also similarly limited in how much they use. This is working remarkably well, we're not experiencing any network related issues at all anymore. But it costs... On Tue, Jul 15, 2014 at 2:00 AM, Tomas Hlavaty t...@logand.com wrote: Hi Henrik, 44KB / second is far from insignificant IMO, it works out to 0.35 Mbit/s if I'm not mistaken, we're paying 20 EUR per month per 1Mbit at our current co-location. Well worth spending a couple of days to avoid permanently. wow, 20 EUR per 1Mbit? 160 EUR per 1MByte? In 2014? I can't believe that. My home connection costs 24 EUR a month without trafic restrictions iirc and is much faster than that:-) Cheers, Tomas -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
