[systemd-devel] Reduce unit-loading time

[Cristian Rodríguez]

On Mon, May 18, 2015 at 7:24 AM, cee1 <fykcee1 at gmail.com> wrote:
> 2015-05-17 17:45 GMT+08:00 Martin Pitt <martin.pitt at ubuntu.com>:
>> Hello cee,
>>
>> cee1 [2015-05-16  0:46 +0800]:
>>> Thanks for the suggestion, it was other processes running in parallel
>>> which presumably consuming lots of IO, after sending SIGSTOP at the
>>> first (and SIGCONT later), the unit loading time is decreased to
>>> ~100ms.
>>
>> You probably want to use some readahead solution. We found that it
>> makes a significant improvement on ARM boards with slow MMC cards.

You could also

posix_fadvise(fileno(f), 0, 0, POSIX_FADV_SEQUENTIAL);
in the bits that load the unit file..the kernel is free to ignore that
advice however.