Why dont they run OS from a chip

[kenimpzoom]

I always wondered, why dont they have a flash memory chip that you keep the OS on.<br /><br />Seems like the computer would run so much faster with the OS on a chip.<br /><br />You would keep a backup of the OS on the hard drive in case of memory failure.<br /><br />Or am I missing something?<br /><br />Ken

 

[rwise]

Re: Why dont they run OS from a chip

an old tandy unit my parents had did have dos 3.3 on ROM, did not seem faster than booting from a hard drive (which they also had with a newer version)

 

[roscoe]

Re: Why dont they run OS from a chip

Because they cant make an os that doesn't need to be tweeked every few months.

 

[chuckz]

Re: Why dont they run OS from a chip

I believe on boot up the operating system is loaded into memory. Loading the operating system from ROM might shorten the boot time, but I don't think it would speed up anything else.<br /><br />Here's why I think the OS is loaded to memory. Remember when DEC was king? To boot a PDP8 you toggled in the address of the paper tape reader. Then you loaded the boot strap loader fron paper tape. Then you loaded the operating system from paper tape. The computer then ran with without needing to access the paper tape.

 

[Ralph 123]

Re: Why dont they run OS from a chip

Well, it depends what you're talking about. Many purpose built computer systems do have the OS in flash. Since they are stable, rigid, purpose built systems it works fine. A Cell Phone or PDA are good examples of these.<br /><br />On general computers, believe it or not, the OS changes a fair amount not just due to bug fixes but also because of peripherals being added, etc. so you have issues about limiting the size of growth, the complexity of needing to manage yet another storage subsystem just for the OS and the cost of all the added circuitry. Non-Volatile RAM is expensive right now too.<br /><br />Now, let's assume you did it, your computer would boot faster but not run too much faster. Why? When your computer boots, it loads the OS into RAM. So, you'd save the time it takes to read the OS from HDD into memory. There are parts of the OS that are loaded on an as-needed basis and you'd save a little time when that happens too.<br /><br />Now, the future is solid-state hard drives (that is, non volatile memory RAM) replacing the electromechanical HDD which is on the order of 100K times slower than silicon RAM. That is why Nanotechnology is so hot right now. That will let you build big solid-state drives cheaply. Then you'll see HUGE speed improvements because you'll be removing one of the biggest bottlenecks in any computer system.

 

[briannh1234]

Re: Why dont they run OS from a chip

The mac used to work that way. But it still had to load a bunch of patches upon bootup.

 

[eeboater]

Re: Why dont they run OS from a chip

I think just about every modern PDA runs like that...

 

[BoatBuoy]

Re: Why dont they run OS from a chip

Ralph is right on. The OS is loaded into memory and then part of it is paged back out, but available. Most other "stuff" is read in and paged back out into the page pool. The apparent response is due to the OS having to recall from the page-pool, on the hdd. If all was in silica, response would be phenomenal.<br /><br />With that said, a great deal of time is spent waiting in the internet to respond. The above scenario would appreciable improve logistic regressions or circuit drawing software for example, but would do very little to improve internet response, Word, Excel, etc.

 

[Scooch_2]

Re: Why dont they run OS from a chip

We have some HP thin clients that run windows XP (embedded) from a rom. The take surprisingly longer to boot than you would expect. They can be updated with OS updates and patches.

 

[Ralph 123]

Re: Why dont they run OS from a chip

Oh that's funny Scooch! <br /><br />How big is the OS storage space? I wonder if what's happening, is the "updates" are actually on the HDD so, every time it boots it loads the old version and then goes to the HDD to load the "new" components. Like double booting! I wonder....<br /><br />Or They must have put so much overhead into the subsystem design to manage it that it crushed any boot speed gain. <br /><br />Oh that's too funny!

 

[kenimpzoom]

Re: Why dont they run OS from a chip

Kinda weird that it has to load the OS into memory every time it boots. Why not keep the OS on a hard drive, update it, then reflash it into permanent memory every month or so. Then have another chip for applications such as microsoft office and IE. The only thing the computer would use the hard drive for would be data.<br /><br />If you change hardware config, you would boot from hard drive, reconfigure, then reflash memory.<br /><br />Seems like some speedfreaks would be doing this.<br /><br />Ken

 

[BoatBuoy]

Re: Why dont they run OS from a chip

Thin clients, and HP is no exception, are typically low end machines. They usually have low to moderate memory and processors significantly shower than most of us would like. <br /><br />The HP thin clients range in processor speed from 533MHz to 800MHz - not blazingly fast by anybody's standard. Their memory complement ranges from 64MB to 256MB, with about an equal amount in flash memory. <br /><br />The XP they, and other thin clients, use is actually XPe, which is who-knows-what. They are absolutely not performance oriented, but price-point oriented instead, with an eye toward total cost of ownership, ease of maintence, and simplicity.

 

[Ralph 123]

Re: Why dont they run OS from a chip

Ken,<br /><br />You load the OS in memory for speed. A HDD is 100,000 times slower than memory. It takes a long time (in computer time) to get data off the HDD. So, you do it once at boot and you're good until you need to reboot (basically). It basically does what you are thinking about - keep the OS in fast memory and just reload it on an as needed basis (eg, when you reboot)<br /><br />NVRAM - non-volatile RAM - ram that doesn't lose data when power is turned off - is VERY expensive. Have you seen the little USB flash drives or Sony Memory sticks or SanDisks - they cost about $100 for say just 256MB. Look how big your windows directory is (in the neighborhood of 3GB) so you'd need 12 just for the OS! That's more than the cost of a whole system these days including a nice LCD flat panel. That's a lot of cake to speed boot time by a few seconds.<br /><br />Now, when you get rid of the HDD all together (coming some day) then you'll see not only faster boot times but faster run times. Every time data is needed (an application, a file, whatever) it would launch instantly -- no waiting for the "slow" HDD to feed the memory.<br /><br />In the mean time, if you want increased speed, put as much RAM into your system as you can afford. That way, the OS can keep more data in memory and needs to go to the HDD less often. The OS has memory management built in to it that tries to keep as much data as possible in RAM through a process called caching

 

[tomatolord]

Re: Why dont they run OS from a chip

I guess becaue windows xp is over 28 megabytes of data - that chip would be very very expensive<br /><br />considering I dont know many home computers that even that much ram to even begin with