Boot charting

[Tollef Fog Heen]

* Phillip Susi 

| The other problem seems to be that readahead-list is only managing to
| pull 25% of my disk's maximum sustained throughput.  According to the
| image it peaks at 25 MB/s, but my raid array is capable of sustaining
| nearly 100 MB/s.  I believe this is because the files that are being
| read are scattered all around the disk, so there are a lot of seeks
| involved which slow down the throughput.

readahead uses filelist-order, which orders the files in the order
they are on the disk.

I am going to make readahead a bit smart too, so it will record the
file list at each boot and then read them back as early as possible.
The current file list is static and hasn't been updated for quite a
while.

-- 
Tollef Fog Heen                                                        ,''`.
UNIX is user friendly, it's just picky about who its friends are      : :' :
                                                                      `. `' 
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