Thanks for you quick answer. Not yet,
For that I will need to switch to fact insertion instead of Java Set. Do you think to will make a difference in the way the RETE Tree will be built ? 2014-03-20 20:27 GMT+01:00 Mark Proctor <mproc...@codehaus.org>: > Did you try using the engine in equality mode? It will only ever allow one > "equal" object to be inserted, others are just ignored. > > Mark > On 20 Mar 2014, at 18:54, Raphael <raphael.joli...@gmail.com> wrote: > > > Hi, > > > > In our project, we use Drools to compute forbidden allocations as input > for > > an allocation problem (for which we do not use Drools BTW). > > > > The constraint of the problem (forbidden operation for given resources) > are > > expressed as drools rules. > > > > We have about > > -200 resources > > -700 operations > > > > Those are the Drools facts. > > We have about 200 Drools rules describing the forbidden allocations > > > > The problem here is that many rules produce duplicates forbids. > > For instance : > > Rule 1 may forbid Op1 on Res1 & Res3 > > Rule 2 may forbid Op1 on Res2 & res3 > > > > Currently the RHS of rules just insert forbids into a pure Java Set (no > fact > > insertion). > > The Set takes care of avoiding duplicates, but still, we feel we could > help > > Drools by giving him a hint that > > all rules are actually producing pairs of <Resource, Allocation> and > that he > > should not try to produce them more than once. > > > > Currently the structure of each rule looks like that : > > > > when > > $resource : Resource(<someconditions>) > > $operation : Operation(<someconditions>) > > then > > globalSet.add(Pair<resrouce, operation>) > > end > > > > With the size of the problem, we often end up with outOfMem/ GC limit. > > When analyzing memory dump, we see about > > 300.000 drools left tuple object. > > > > I am not sure if we could help drools to reduce the Rete tree here. > > I mean, the allocation matrix is already : 200*700 = 140.000 cells. > > Drools only uses 2 nodes for each possible forbids, which seems already > well > > optimized. > > > > We had several idea to improve that though, but we are not enough expert > in > > the internal of the RETE algorithm to decide if that's a good way to go : > > > > 1) Insert forbids as facts in the RHS and check they are not already > there > > in the LHS : > > when > > $resource : Resource(<someconditions>) > > $operation : Operation(<someconditions>) > > not Forbid(res=$resource, op=$operation) > > then > > insert(Forbid($resource, $operation)) > > end > > > > 2) Merge all rules in one big rule with a single RHS > > Is it possible to have something like : > > when > > // Rule 1 > > ($resource : Resource(<someconditions>) > > $operation : Operation(<someconditions>)) > > or > > // Rule 2 > > ($resource : Resource(<someconditions>) > > $operation : Operation(<someconditions>)) > > // Etc ... > > then > > globalSet.add(Pair<resrouce, operation>) > > end > > > > 3) Define a common RHS somewhere and tell Drools all rules use this one. > > Is there a possibility in Drools to define reusable RHS ? Would it help ? > > > > 4) Any other idea ? > > > > > > Thanks in advance for your help. > > Brgds, > > > > Raphael Jolivet > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > View this message in context: > http://drools.46999.n3.nabble.com/Needs-advice-to-help-Drools-on-a-big-problem-and-avoid-GC-overhead-tp4028838.html > > Sent from the Drools: User forum mailing list archive at Nabble.com. > > _______________________________________________ > > rules-users mailing list > > rules-users@lists.jboss.org > > https://lists.jboss.org/mailman/listinfo/rules-users > > > _______________________________________________ > rules-users mailing list > rules-users@lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users >
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