# Re: \[PATCH v3 0/5\]add new ioctls to do metadata readahead in btrfs

- From: David Nicol \<hidden\>
- Date: 2011-01-19 21:33:48 
- List: linux-api
- Page: https://ratatoskr.run/linux-api/2011/01/50411
- Thread: https://ratatoskr.run/linux-btrfs/2011/01/50402/t.md

```text
On Wed, Jan 19, 2011 at 2:34 PM, Andrew Morton
[ref] wrote:

> It would be much more valuable if those 3.5 seconds were available to
> devices which really really care about bootup times, but very few of
> those devices use rotating disks nowadays, I expect?

And don't rotating disk modules read and buffer whole tracks, doing
their own readahead, anymore, anyway? Isn't that part of what "on-disk
cache" does?
```