Thanks. I'll give this a try.
Greg Barton wrote:
Edson's advice on this issue is spot on, but if you want a more
incremental approach you may try this: optimize your hierarchy test. A regex string match
is not the fastest thing you could do to check what level the rule is in, and that test is
the one done most frequently. (It's in every rule, and should be the first condition
in the LHS, right?) So some targetted optimization, if possible, could be helpful. Could
the hierarchy indicator be an array of integers? The test for integer equality is orders
of magnitude faster than regex.
obj(level == 1, level == 2, level == -1) //-1 indicates unset
objSetLevel(2, 1); //Set level == 1
Yes, messy looking, but probably a lot faster than regex.
And as for the "changing the contents of the object and doing the update is not good
for drools performance" idea, I guess it matters what your purpose is. Changing the
contents of objects and having the rules react to that change is what rules are for. :)
If this is something you intend to avoid you might want to look at sequential mode
--- On Mon, 4/13/09, Charles Binford <Charles.Binford(a)sun.com> wrote:
> From: Charles Binford <Charles.Binford(a)sun.com>
> Subject: [rules-users] How to traverse a hierarchy?
> To: "Rules Users List" <rules-users(a)lists.jboss.org>
> Date: Monday, April 13, 2009, 4:56 PM
> All, I'm trying to figure out a better way to solve
> this problem. I
> have a batch of objects that I want matched against a
> hierarchy of
> rules. I check the rules in order, and as soon as I find a
> match I'm
> done for that level of the hierarchy. In other words, If
> the object
> matches a rule, we'll check the rules children, but not
> the siblings.
> rule 1
> rule 1.1
> rule 1.2
> rule 1.2.1
> rule 1.2.2
> rule 1.3
> rule 2
> If an object matches rule 1, check for a match at level
> "1.*", but rule
> 2 will never be checked. If an object matches 1, 1.2, and
> 1.2.1, we're
> done as 1.2.1 has no children.
> My current implementation with drools works, but is very
> inefficient. I
> have a "level" string in the objects and whenever
> I find a match I
> update the level of the object and force an object update.
> Each rule
> tests that the level string is correct, e.g. rule 1.2.1
> works as follows:
> rule "1.2.1"
> obj(level matches "1.2.*",.....)
> I'm also using saliance to keep the evaluation order
> like I want it.
> Changing the contents of the object and doing the update is
> not good for
> drools performance as I understand it so I'm looking
> for a better way.
> The hierarchy and the order of the matching is key to my
> application so
> I'm not wanting to redesign that part of things.
> I tried using activation-groups. That worked great as long
> as I only
> had a single object to run through the hierarchy, but given
> the way the
> rest of the system is design I need to load up 10-100
> objects before
> each call to fireallrules() for performance purposes.
> Any suggestions are appreciated.
> Charles Binford
> rules-users mailing list
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