On Fri, Feb 27, 2009 at 11:11:35AM -0700, Wilton Helm wrote: > >Again, the main reason for me to require a higher end CPU is audio > >compression. But I also want the system to be run by a standard OS. It > >needs to be easy to add your own application there. > > > Mutually exclusive. I don't know any standard OS that doesn't waste > about 10 x as many CPU cycles as a SIP phone should ever need.
It's not about what is wasted. It's about what you're left with. Anyway, my new home PBX is an Alix (alix6b2) unit: http://www.pcengines.ch/alix6b2.htm It's running Debian Lenny. chao:~# cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 5 model : 10 model name : Geode(TM) Integrated Processor by AMD PCS stepping : 2 cpu MHz : 498.056 cache size : 128 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu de pse tsc msr cx8 sep pge cmov clflush mmx mmxext 3dnowext 3dnow bogomips : 998.10 clflush size : 32 power management: chao:~# free total used free shared buffers cached Mem: 256640 251900 4740 0 78488 145972 -/+ buffers/cache: 27440 229200 Swap: 224868 52 224816 It also has an openvpn link, an Astribank device and the network of my very small LAN. Its standard load avarage is, well, 0. I never even bothered optimizing it. > The > problem is generalization. A standard OS is designed to support a > wide variety of devices, including a wide range of screen sizes. > The abstraction layers that make this possible often consume more > CPU resources than the application they are supporting. Most of that > isn't needed for this application. Compatibility with WXVGA isn't > required. Even a full blown file system is a luxury. Ask yourself how all those small mp4 players even work. I suppose most of them run Linux. See also http://www.rockbox.org/ > > Linux is about the closest thing because it can be pared down. But it > takes someone with considerable experience to know how and what to > trim. I supervised a system that used "busy box" to create a compact > system that lived on a small flash card an some RAM. This trimming can also be automated, if I see that a standard distribution will not do. See e.g. http://astlinux.org/ . > > As an example, I have been a Palm owner for a number of years. I > laughed when the Win CE stuff came out to compete. The Palm OS was > written for the task at hand. I could go a week or more on a charge. > The Win CE devices had to be recharged after 8 hours! Why? The OS > required too much which required far more compute power, which ate > batteries. The device does not run on batteries. The plug I mentioned above is 5W. Here's what happens when someone starts optimizing the power consumption: http://www.rowetel.com/blog/?p=61 Anyway, a general-purpose OS consumes extra memory, but relatively little power. I expect that a SIP phone (Requiring transport of many small packet => many interrupts) is a large power consumer. > > The SIP phone you propose could be done with about 1 W of power plus > a couple more for backlighting. An OS based version would start at > 5 W + backlight And this is based on? > and could easily go to 15 W or higher. Not the end of the world, > I suppose on a desk (if there aren't a hundred of them and I'm not > paying the electric bill) but a huge difference if it has to run > on batteries. -- Tzafrir Cohen icq#16849755 jabber:[email protected] +972-50-7952406 mailto:[email protected] http://www.xorcom.com iax:[email protected]/tzafrir _______________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
