[elephant-devel] Re: Some performance optimizations

[Alex Mizrahi]

 > Work on a new cursor implementation is in progress, that
 > might come later.

done, at least passes all tests..

of course this new implementation doesn't solve all issues, but at least 
cursor operations now do not slow down with table growth, to the extent 
PostgreSQL does not.

btw, i've found such test:

(test (map-btree-remove :depends-on (and btree-make btree-cursor map-btree))
  (flet ((mapper (k v)
    (declare (ignore k))
    (when (and (>= (slot1 v) 100) (< (slot1 v) 200))
      (remove-current-kv))))
    (map-btree #'mapper bt)

seems kinda weird for me -- cursor-delete (which is called from 
remove-current-kv) -- leaves cursor uninitialized, so further cursor-next 
does cursor-first (looks like it's not documented for Elephant, but that's 
the way it works in bdb.
so it starts again from start to reach these deleted values again..

won't it be better to define something like:

(defun remove-current-kv ()
  (unless *current-cursor* (error "Cannot call remove-current-kv outside of 
a map-btree or map-index function argument"))
 (multiple-value-bind (f k v)
 (when f
  (cursor-current *current-cursor*)
  (cursor-delete *current-cursor*)
  (cursor-set-range *current-cursor* k))))

?

btw tests helped me debugging thing a lot..