On Tue, Mar 22, 2005 at 07:53:37PM -0500, Lee Revell wrote: > The solution is fairly well known. Rather than treating the zillions of > disk seeks during the boot process as random unconnected events, you > analyze the I/O done during the boot process, then lay out those disk > blocks optimally based on this information so on the next boot you just > do one big streaming read. The patent side has been discussed and there > seems to be plenty of prior art. > > Someone needs to just do it. All the required information is right > there.
Some of the folks on our desktop team have been doing a bunch of experiments at getting boot times down, including laying out the blocks in a more optimal manner, allowing /sbin/readahead to slurp the data off the disk in one big chunk, and run almost entirely from cache. The results are quite impressive, though the absense of any kind of tool to reorganise the layout means that once a few packages are installed/removed, the layout is no longer optimal. This old mail: http://marc.free.net.ph/message/20040304.030616.59761bf3.html references a 'move block' ioctl, which is probably the hardest part of the problem, though I didn't find the code referenced in that mail. Andrew ? With something like this, and some additional bookkeeping to keep track of which files we open in the first few minutes of uptime, we could periodically reorganise the layout back to an optimal state. Dave - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
