[development] Split up the cache table

[Gerhard Killesreiter]

Gerhard Killesreiter wrote:
> 
> Total weighted average:
> 
>          SELECT    INSERT
> Now       0.003     0.007
> Test 1    0.010     0.011
> Test 2    0.007     0.008
> 
> There is a marked improvement here.

Moshe pointed out that it is now clear what is what.

"Now" is with the "split cache patch" applied. "test 1" is stock 
Drupal-4.7-CVS aka 4.7.3, "test 2" was with the patch for extra caching 
of forum blocks and navigation applied.

And of course: all times are given in seconds (mea maxima culpa).

In other words, with this patch applied the average cache_get was faster 
by a factor of three. I think this pretty much kicks ass and we should 
get this patch applied.

I'll bring it up to date and will incorporate the suggestions I got if 
our Maximo Lider agrees that the patch is a sound idea.

Cheers,
	Gerhard