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?