KSyCoca, Thread safety, and Cache invalidation

[Thomas Lübking]

On Dienstag, 14. Juli 2015 19:00:14 CEST, Milian Wolff wrote:
> On Tuesday, July 14, 2015 11:49:25 AM David Faure wrote:
>> On Friday 26 June 2015 18:03:00 Frank Reininghaus wrote: ...
>
> It has. Querying the current time repeatedly is quite costly, 
> and often shows 
> up in code that extensively uses timers, or 
> QDateTime::currentDateTime() etc.
>
> But it's probably still cheaper than querying on-disk meta data 
> in the worst 
> case, esp. on old rotary disks.

Actually, checking currentTime() is already the problem here (causing the IO for the timezone stuff), see http://marc.info/?l=kde-core-devel&m=143533622526705&w=1 (the 1st paragraph part of my comment somehow turned into a second-level quote)

Comparing a monotic timer (QElapsedTime) is however - at least on linux - close to cost free PLUS: one can have an entirely free "do not check again during this event cycle" flag.

Cheers,
Thomas