[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: Parallel Booting



On Fri, 2007-07-06 at 18:17 -0400, Alan Cox wrote:
> On Fri, Jul 06, 2007 at 05:56:35PM -0400, Colin Walters wrote:
> > Ok, I just googled and found a really good thread:
> > http://kerneltrap.org/node/2157
> > 
> > It's unclear to me though how much of this is actually running now.
> 
> Quite a bit in terms of the disk layer. We readahead and writebehind,

As I understand the readahead, it is simply requesting further blocks
inside a single file before the read() requests come in for them. 

The Hot File Clustering system on that page actually moves the files
into a special area of the disk and and ensures they're contiguous (thus
avoiding seeks, which plain readahead doesn't really solve).

Both OS X and Windows include systems which watch the startup and
continually optimize.  Looking at Fedora, we have the "readahead"
package, but as far as I can tell it's static in the sense that we ship
some definitions with the package; it's never rerun.  


Has anyone run a current version of http://bootchart.org/ on Fedora?



[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]