I had a look at my
bootcharts and something seems to be wrong with them. The
ureadahead process does what it's supposed to do (disk utilisation is 100% most of the time), but it also blocks any other action.
Since I've got a slow, laptop harddrive,
ureadahead itself takes ~50s of the boot time. Then, the rest of the visible boot sequence takes another 100s to complete, using a lot of CPU, but not maxing it out and lots of IO (again, 100% almost all the time).
This seems just strange to me. Is my
ureadahead misconfigured? Why does it block tasks like bringing up the network which seems to be taking lots of cpu? Should it take ~50% of the bootchart time in general?
Edit: here is the example bootchart: http://img191.imageshack.us/img191/1049/localhostkarmic20100815.png (or this if the direct one didn't work: http://yfrog.com/f/5blocalhostkarmic20100815p/ )