The reason I want compiled-in drivers is to make start up a bit faster. I may be wrong but if I have to wait till everything else comes up before I can load essential drivers and I can shave a couple of seconds off boot time, that's a good thing. AFAIK, USB power doesn't come up until the drivers are loaded. So why not build them into the kernel?
>From what I've read, the OS system clock's resolution (not a hardware timer) is part of the kernel. usleep() in 2.4 uses a 100 Hz clock. 2.6 allowed you to specify a resolution. Early versions used a 1 kHz clock but that was later lowered to 250 Hz to give longer time slices to running processes.
As for cold shutdown, I'd rather have a file system that attempts to handle it than one such as EXT2 that forces you to do a lengthy and unpredictable fsck. Plus, even if you're lucky enough to have a short fsck, the system reboots which at least doubles the boot time. Unless there is a facility built into the OS that allows you to inform the user what's going on without a terminal connected, the non-computer user will think the product is broken. In my particular case, my write operations are very short and very infrequent (preferences, basically) so I'm not overly concerned that there might be an error. But without EXT3, I'm SOL on a boot time faster than 10 seconds. And, IMHO, for a non-technical user, 10 seconds without knowing what's happening is an eternity.
Take a DVR as an example of an Linux-based appliance. When you turn the thing on and it needs to check the disk, there's little or no feedback on how long that's going to take. Should I start to get comfortable on the couch or should I go wash the garage while I wait?
But if graceful shutdown is the best way to go, then IMHO, the boards should have power-sense circuitry with a super-capacitor or something on them that would hold just enough juice to execute a shutdown which would be triggered by an IRQ generated by the power-sense circuitry detecting voltage below operating levels. The TS-BATT is too expensive, IMHO.
--- In
m("yahoogroups.com","ts-7000");">.com, Peter Harrison <cheetah100@
...> wrote:
>
> On Tue, Dec 22, 2009 at 9:20 AM, Blair <..> wrote:
> > My personal wish list for a 7260 includes the following:
> >
> > 1) Fast boot and power-loss tolerant file system e.g. EXT3. Why? My goal is to build an appliance that places no demands on the user to gracefully start up or shut down. Flip a main power switch on or off and expect it to come up quickly and in a predictable amount of time. The user should also be able to disconnect the battery powering the system without concern that it's going to take more than the normal startup time to reboot.
>
> Cold shutdown is difficult to solve. Main thing is flushing writes so
> the system is in a consistent state.
>
> > 2) Compiled-in USB drivers, not modules.
>
> I would settle for working USB ;) Any reason for compiled in over
> modules? Assuming the modules work and are stable?
>
> Reason is that compiled in will mean a bigger memory footprint for
> those who don't use those features.
>
> > 3) 2.6.whatever is most recent and stable.
>
> Seconded.
>
> > 4) Working 802.11
>
> Seconded.
>
> > 5) Higher resolution system clock. IIRC, 2.4 used a 100 Hz clock and 2.6 uses 250 Hz. IIRC, you can build it to run at 1k Hz.
>
> Isn't this a hardware issue?
>
Get a great deal on Windows 7 and see how it works the way you want.