Admun's Tech Journey

thoughts, ideas, projects, and discoveries on technologies

  • Main
  • Tag Cloud
  • Archives

28

Feb

p2p my TV

Posted by Admun  Tags: p2p, tv
I guess I am not that crazy after all when I think of this and this. p2p for content is the future, IPTV is just the start.

At least Robert X. Cringely think so too, quoted "... How big a data center do you need before you realize that no data center is big enough for some applications? Only a server-server or peer-to-peer architecture makes sense in the long run... ...Google and its distributed shipping containers might be right for this moment or next, but they can do the math and that math tells them that pumping tens of millions of simultaneous HDTV unicasts from a Google server is no way to make money. It is much better to use Google servers to seed video content, which is then shared by many peers...."

Rob did a much better job laying out how the market model works using Grid Networks (never heard of and can't find link.....) and iTunes as example.

Since I am heading to China soon, maybe I should really try out streaming TV from home in Ottawa to whereever I am. It will be cool to watch TV from thousand of miles away. cool
Leave a comment

09

Feb

Disappointed Tero

Posted by Admun  Tags: cdma, cellphone, palm
Tero @ Centrepointe

Since I come back from Boston, I've been using this PDA phone. I have the (un)pleasure to use a Kyocera before I get this Treo. Both of them are based on PalmOS, which is showing sign of not keeping pace with the product evolution, IMHO.

The reason this PDA is issue to us is to generate traffic on our CDMA 1xRTT live-air test network. So, it is important to run application that generate network traffic, a lot of them. The PDA has a few network applications installed, I often running Varichat (a IM client) in the foreground. On the other hand, a mail program is running in the bakground. The mail program swap to the foreground every few minutes to check for new mail. It returns to the background after it completed and the Varichat continues taking foreground. From a user point of view, this is annoying becasue the mail program keep distrubing user chatting on the IM client. Desplit of user annoyance, the application swapping is slow and create an opportunity for race condition. More than once I notice the PDA crash after the swap. The swapped out application is performing an operation that cannot be disrrupted, which result in fatal crash. For Tero, the failure handling has improved in PalmOS 5 that it automatically reset when encounter fatal problem.

PalmOS was designed for a small handheld device with a 33mhz CPU (Moto Dragonball) and 128k memory onboard. For such a limited system, the OS has to cut a lot of corners to fit itself into it. One such thing is a full functioning process scheduling subsystem. In many modern OS, we can often find a multi-tasking engine inside to manage program execution. Programs runs in a isolate enviroment and in a concurrent fashion.

However, PalmOS does not have such a process execution environment; Since there is no need for executing more than one application at a time on the original Palm, PalmOS is designed to give application CPU timeslice by swapping in/execute/swapping out. An application can generate an event to demand execution time. This event can trigger at anytime, and the current application might be in a critical region of execution. This result in fatal error on re-entry.

I hope the future version of PalmOS will finally introduce a proper multi-tasking execution engine. It is much needed for a PDA with rich functionality and network capability.

I just returned this PDA phone as I am going to be out of town soon until end of summer, hopefully we might get some new PDA phone to deploy that have better OS.

<update>
Did some reading on PalmOS 5 that is on th Treo, it seem to have the some sort of multi-tasking capability (as they claim). But I heard it from a palm developer that the same foreground/background issue still exist.
</update>
Leave a comment

About Me

admun My passion has always been on software development, and I know it since I wrote my first program on an Apple II. I worked on cellular wireless system in the past (C/C++) and now focus on web application (LAMP, PHP, MySQL, CakePHP, Symfony, jQuery, Google AppEngine/python).

Tags

abit android apache app engine audio bandwidth benchmark bing blogroll bluetooth boinc bookmark botnet bt cakephp cdma cellphone chinese chrome clouds coding crash crawler date dns drm dsl fedora friendster g1 gaim gdesklets gmail google grid h323 hardware html ie6 instant messaging internet javascript jquery language lifestreaming linux liunx meetup ming motorola msi mysql nas nat networking nokia ntp nucleus opinion optimization os p2p palm parrot php power reblog redhat regex rss sdk se search security shell skype social network spam stats string svn syntax sysadmin t-mobile teksavvy telecom thinkpad time tips tuning tv twitter unix voip web web app web2.0 webos wordpress

Archives

  • Full archive
  • May, 2013
  • Feb, 2013
  • May, 2012
  • Aug, 2011

Search

Powered by LMNucleus CMS v3.66 | Copyright Edmond Hui
This page takes 0.050 sec/27 queries to process | NP_BadBehavior blocked 334 spams for the past 7 days
Theme Design by short funny jokes | Ported to Nucleus CMS by BABOCHTA
[Valid XHTML 1.0 Strict]