I'm improving the Dllist in these direction:
1) Avoid "if" statements in insertion/remove phase, for instance now the
AddHeader appear like this:
void
DLAddHead(Dllist *l, Dlelem *e)
{ Dlelem *where = l->dll_master_node->dle_next; e->dle_next = where; e->dle_prev = where->dle_prev;
where->dle_prev->dle_next = e; where->dle_prev = e;
e->dle_list = l;
}
2) Not using a malloc but using a "special" malloc that not perform a malloc for each request but do a BIG malloc at
firstrequest...
In the file dllist.h is not clear what is the public part and the private
part
of the implementation in particulary I see that somewhere in the code
there is the assumption that an Empty dllist is "zeroed" instead of
use DLInitList, for example this is the way to initialize a struct that
contain a Dllist itself:
cp = (CatCache *) palloc0(sizeof(CatCache) + NCCBUCKETS * sizeof(Dllist));
this break my optimization because in my implementation a
dllist is
typedef struct Dllist
{ Dlelem *dll_master_node;
} Dllist;
and not anymore:
typedef struct Dllist
{ Dlelem *dll_head; Dlelem *dll_tail;
} Dllist;
and is empty if list->dll_master_node->dle_next and
list->master_node->dle_prev are pointing to
list->master_node ( previously allocated in DLInitList).
What should I do ? Forget the point 1) ?
Regards
Gaetano Mendola
