Willy Tarreau <w@xxxxxx> wrote: > Hi Elias, Hi Willy, > > On Tue, Feb 26, 2008 at 12:56:31AM +0100, Elias Oltmanns wrote: > > [ very interesting project ] > >> Probably, the major problem is that I don't really know what kind of >> applications (apart from shock protection) I should be thinking of that >> might want to have a queue freezing facility at hand. > > In terms of applications, depending on the sensitivity of the accelerometer, > we can imagine that a laptop would immediately force unmount crypted > filesystems if it believes it's being stolen, for instance. It's just a > random idea that comes to my mind, in the hope it may help you imagine > some crazy usages. Well, this application would use the same input data (acceleromtere) but it would certainly not require a generic queue freezing facility. > But generally you should not fool your mind with too many hypothetical > cases, ideas will come once you provide a smart interface and this > interface will evolve with future needs. > > Concerning your daemon, I think that every millisecond counts when a > laptop falls on the floor. So I think that running it in the kernel > should help you gain those precious milliseconds. The idle immediate command itself may need up to 300 milliseconds to complete according to the ATA standard. This seems like a very long time compared to CPU standards, i.e., the time usually needed to serve a lightweight daemon. > I doubt your daemon could trigger fast enough while X is starting or > during some activities which require a lot of CPU or uninterruptible > I/O. On my system the daemon's response *feels* just fine even while compiling a kernel; I haven't done any measurements or benchmarks though. The thing I'm most concerned about is uninterruptible I/O but I'm not quite sure whether and how this can be addressed in kernel space. Regards, Elias - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
