Faster Boot by logging startup
The actual boot-time of ubuntu desktop is limited by the amount of files accessed in the boot process (around 10.000 files spread in the disk. 10.000 files, at 8-18ms seek-time is equal roughtly to 100sec.).
The Apple-Macintosh is a good approach for solving the problem: MacOS-X maintains a file with a 'log' of files in userland accessed by the boot proccess. The MacOS-X boot way is: load the 'log' and start to 'touch' every file in 'elevator'-way (touch from the lowest cluster to the highest cluster) allowing them to stay in cache. this way, the services initiated later, will be blessed by the cache and, ideally, all the 'disk work' will be sequential-read. At the end of the proccess, the 'log' will be updated (for example, a new service installed and boot-started by the first time).
Ideally, this will be implemented all in userland, without touch the kernel.
Blueprint information
- Status:
- Complete
- Approver:
- None
- Priority:
- Not
- Drafter:
- None
- Direction:
- Needs approval
- Assignee:
- None
- Definition:
- Obsolete
- Series goal:
- None
- Implementation:
- Unknown
- Milestone target:
- None
- Started by
- Completed by
- Scott James Remnant (Canonical)
Whiteboard
Not an appropriate spec for Upstart, re-register for Ubuntu