[devel] [PATCH 0/3] optimize rpmsetcmp()

[Alexey Tourbin]

On Sun, Dec 05, 2010 at 02:26:44AM +0300, Dmitry V. Levin wrote:
> On Sun, Dec 05, 2010 at 12:28:31AM +0300, Alexey Tourbin wrote:
> [...]
> > What you urge to do is to cut down the price even more.  But there is
> > clearly something wrong with apt, as it tries to resolve every single
> > dependency upon every startup.  And, fortunately, it takes only a few
> > seconds!
> 
> It will take twice or trice longer time when _all_ packages with ELF
> files will get their set-versioned dependencies, so I expect apt-get
> startup will eventually be about 10x slower again (compared to 5.1 branch).
> 
> apt-rpm indeed calls rpmRangesOverlap() too many times, it's common
> knowledge.  Unfortunately, stating this fact isn't sufficient to make
> apt-rpm work faster.

So what do you think?  There's a possibility to change bitv[] to bitmap,
per Kirill's proposal.  That mighit yield about, say 30% user time cutdown.
However, note that apt is not only eager for user time.  System time is
being spent with splendor as well.

Personally, I like bitv[], and I don't like something like <sys/select.h> stuff.

> -- 
> ldv