Re: About ceph_clock_now()

[Willem Jan Withagen <wjw@digiware.nl>]

On 22-1-2016 17:00, Erwan Velu wrote:
> Hey,
> 
> I've been able to continue this work and updated by branch accordingly.
> I understand the benefit of using the ceph_time work but I feel that it makes the change pretty verbose for a not a so big change (CLOCK_REALTIME vs CLOCK_MONO).
> 
> This imply a change of all utime_t and makes the computations a little bit more complex to read.
> 
> Does it worth the time spent on it ? If yes, I don't have any issue continuing this way.
> I'm pretty new to the project and would like to make the best PR as possible.
> So your insights on the under-work patch would be very helpful.

Erwan,

It would be real useful if references to CLOCK_(MONOTONIC|REALTIME)_*
are centralised in one place (or at least as little as possible).
And perhaps wrapped in simple function.

Reason is that CLOCK_*_COARSE are linux specific.

POSIX only has CLOCK_*, without the COARSE.
FreeBSD has the CLOCK_*_FAST variant which equals the COARSE objective.
(less accuracy, more speed)

So I've wrapped the code in a
#if defined(__linux__)
#	USE the COARSE variant
#elif defined(__FreeBSD__)
#	USE the FAST variant
#else
# 	Use the POSIX version as fallback
#endif

Thanx,
--WjW