[systemd-devel] Improve boot-time of systemd

[Chen Jie]

2011/3/18 Kay Sievers <kay.sievers at vrfy.org>:
> On Fri, Mar 18, 2011 at 14:40, Gustavo Sverzut Barbieri
> <barbieri at profusion.mobi> wrote:
>> On Fri, Mar 18, 2011 at 10:52 AM, Andrey Borzenkov <arvidjaar at mail.ru> wrote:
>>> On Fri, Mar 18, 2011 at 12:35 PM, fykcee1 at gmail.com <fykcee1 at gmail.com> wrote:
>
>>>> 1. What can readahead affect boot-time?
>>>> Sadly observed negative affect -- boot-time increases at least 1s.
>>>
>>> From subjective feelings (no real measurements) I confirm it.
>>
>> I noticed it as well, even with my Macbook Pro i7 with 8Gb RAM and
>> 128SSD using btrfs.
>
> It's ~0.5 sec faster here with readahead on a SSD.
Each time runs readahead-replay may cause readahead-collect to record
more blocks to read ahead -- size of "/.readahead" never reduces.

Also I found "/.readahead" recorded files like ".xession-errors" which
is written only, thus should not be read ahead.

Maybe adjust readahead-collect-done.timer to 5s will help.