Re: [rules-dev] Lazily Enabled Truth Maintenace (Project Propsoal)

You're not alone in wanting to see the changes... It'd be good if Leo would be willing to post his experience as a comment on the original blog http://blog.athico.com/2010/09/lazily-enabled-truth-maintenace.html It might help others wanting to get involved. ------------------------------ *From:* rules-dev-bounces(a)lists.jboss.org [mailto: rules-dev-bounces(a)lists.jboss.org] *On Behalf Of *Mauricio Salatino *Sent:* 20 September 2010 23:18 *To:* Rules Dev List *Subject:* Re: [rules-dev] Lazily Enabled Truth Maintenace (Project Propsoal) nice, is it working? I would like to see the changes in the commits.. Greetings. On Mon, Sep 20, 2010 at 7:09 PM, Mark Proctor <mproctor(a)codehaus.org&gt;wrote: > On 20/09/2010 21:58, Leonardo Gomes wrote: > > Ok, it took me much longer that I had thought, but I think it's working > now.. all tests passing except for ReteooWorkingMemoryTest that does: > > FactHandle fd = workingMemory.insert( string ); >> >> assertEquals( 1, >> tms.getAssertMap().size() ); >> > > Which is a good sign, since tms is now empty as long as you haven't done > any logical insert :) > > I implemented just the first part of your suggestion, with a boolean. I > will try to implement the solution with the counter later this week and > maybe do some adjustments before submitting a patch. > > Do you have any suggestion in terms of unit tests that you would like to > see or just the apparent lack of regressions is enough? Well, I can also > think of some tests by taking ReteooWorkingMemoryTest as an example, in case > you don't have anything particular in mind. > > When you do some insertions cast to get some of the internal data > structures and check the equality map is null, maybe check the OT confs are > false, do a logical insertion check it can turn on for specific OTNs and not > all and that it correctly adds all objects for the OTN. This will be > important for the next stage of the work. > > Mark > > > Cheers, > Leo. > > > > > On Mon, Sep 20, 2010 at 5:14 PM, Mark Proctor <mproctor(a)codehaus.org&gt;wrote: > >> On 20/09/2010 15:53, Leonardo Gomes wrote: >> >> I think I wasn't quite clear in my last email, so let me try to >> reformulate it: >> >> I also gave it a try to try to do what you suggested here ( >> http://blog.athico.com/2010/09/lazily-enabled-truth-maintenace.html), >> Mark, and couldn't make it work due to the following situation: >> >> 1) Current code seems to rely on the equality map to know that a logical >> insert (insertLogical) for an object that has already been regularly >> inserted (insert) should be ignored; >> >> You would need to lazily maintain an equality map. When the first logical >> insertion is done we will have to first populate that map from the Object >> Type Node set of FactHandles. >> In the "insert" one of the first lines is: >> ObjectTypeConf typeConf = this.typeConfReg.getObjectTypeConf( >> this.entryPoint, >> >> object ); >> >> So we get the ObjectTypeConf before we do anything with the object >> itself, and we can check if TMS is being maintained for that Object Type. >> >> >> 2) If I apply the modifications that you suggested, from what I >> understood, things would start to be put in the equality map only when a >> logical insert is issued; >> >> *Problem*: How would I handle the situation described in item 1, if I >> don't have anything in the equality map at the moment a logical insert comes >> in and I have to "lazily activate" TMS? >> >> final Rete source = this.ruleBase.getRete(); >> ClassObjectType cot = new ClassObjectType( MyClass.class ); >> Map<ObjectType, ObjectTypeNode> map = source.getObjectTypeNodes( >> EntryPoint.DEFAULT ); >> ObjectTypeNode node = map.get( cot ); >> final ObjectHashSet memory = (ObjectHashSet) workingMemory.getNodeMemory( >> node ); >> >> That "memory" is the set of currently asserted objects for that OTN. You >> can now iterate that and populate the equality hash map. This is a one off >> as the flag will be set on the ObjectTypeConf from then on and all objects >> will be added to the equality map at the point of insertion. >> >> Does that help? All the information is there, you should have to know how >> to retrieve it :) We don't currently maintain TMS for anything other than >> the default entry point. Although I think that was a mistake and we will >> probably move all entrypoints to work with same, but for now you can ignore >> that and just focus on the default. >> >> Btw this should not be confused with "equality" mode where the equality >> map has to be maintained by default from the start. Some would argue that a >> rule engine should only under work and understand on the bases of equality >> and thus all users must implement hashcode and equals correctly... >> >> >> -- >> >> Moreover, I'm willing to attempt to implement the left and right >> un-linking and tried to start with this easier task to start to get familiar >> with drools-core. I already read the article you linked and your article. >> Would you have any document with an overview of the way drools implements >> rete? >> >> not really no, Rete has already well documented in a number of papers. >> The best thing to do is get onto irc and talk directly to edson and I and we >> can walk you through classes. >> http://www.jboss.org/drools/irc.html >> >> Mark >> >> >> Thanks in advance! >> >> Cheers, >> Leo. >> >> >> >> >> >> >> On Sat, Sep 18, 2010 at 3:49 AM, Leonardo Gomes < >> leonardo.f.gomes(a)gmail.com&gt; wrote: >> >>> if you look at the AbstractWorkingMemory insert method you'll see one >>>> argument is whether it's a logical insertion or not. You'll also see it >>>> check the global maintainTMS configuration and also retrieve the >>>> ObjectTypeConf. So between those things someone should be able to get it >>>> working. >>>> >>> >>> Today, it enters a block where it operates on the equality map and also >>> creates a default handle based on that TMS global option and *regardless* of >>> whether it's a logical insert. >>> >>> If I'm *not* putting things in the equality map for regular inserts, >>> when a logical insert comes in, but there were already stated inserts, how >>> will I know that? I would create a new handle for the logical insert and do >>> the tms.addLogicalDependency(...), even tough there were regular inserts >>> before and this seems to be a wrong behaviour. >>> >>> Apparently, today, you can disable TMS and still use logical inserts in >>> your drl, what, I believe, will lead to inconsistent behaviour, but you're >>> at your own risk. >>> >>> Ideas? I feel that I missed something :) >>> >>> Cheers, >>> Leo. >>> >>> P.S.: I reached the conclusions above based on the fact that >>> LogicalAssertionTest started failing after I did the changes you suggested. >>> >>> >>> >>> >>> On Wed, Sep 15, 2010 at 3:47 PM, Mark Proctor <mproctor(a)codehaus.org&gt;wrote: >>> >>>> On 15/09/2010 14:35, Michael Anstis wrote: >>>> >>>> Is this in drools-core; or drools-compiler? >>>> >>>> Whilst not undertaking to do the work; have a purpose to nose through >>>> the code makes understanding easier. >>>> >>>> It's all in DroolsCore. >>>> >>>> It's a 5 minute hack for me and then 15 minute unit writing test. But I >>>> thought I'd write it up in a hope to bring someone else into the fold, we >>>> need more help writting the core engine someone else out there must want to >>>> work on current edge engine design :) >>>> >>>> if you look at the AbstractWorkingMemory insert method you'll see one >>>> argument is whether it's a logical insertion or not. You'll also see it >>>> check the global maintainTMS configuration and also retrieve the >>>> ObjectTypeConf. So between those things someone should be able to get it >>>> working. >>>> >>>> Mark >>>> >>>> >>>> On 14 September 2010 16:47, Mark Proctor <mproctor(a)codehaus.org&gt;wrote: >>>> >>>>> Here is another project proposal, this time simpler. I think this one >>>>> has Wolfgang's name on it ;) >>>>> >>>>> http://blog.athico.com/2010/09/lazily-enabled-truth-maintenace.html >>>>> >>>>> Three weeks ago I posted the project idea for "Left and Right >>>>> Unlinking"<http://blog.athico.com/2010/08/left-and-right-unlinkin...;. >>>>> So far there are no takers, so if you are interested let me know :) >>>>> >>>>> In the meantime I tried to think of a simpler enhancement that we >>>>> would like to see done. >>>>> >>>>> At the moment Drools has a user setting "MaintainTMSOption" which can >>>>> be true or false. It's a small optimisation that when turned off avoids >>>>> using the equality hashmap that is maintained for all inserted objects. >>>>> >>>>> It would be a much better idea to remove this configuration setting, >>>>> thus simplifying things for end users and have TMS lazily enabled on demand. >>>>> >>>>> For each object type there is an "ObjectTypeConf" configuration object >>>>> that is retrieved every time a working memory action, such as insert, is >>>>> executed. The enabledTMS boolean should be moved there, so there is one per >>>>> object type, by default it is false. >>>>> >>>>> When a working memory action occurs, like insert, it retrieved the >>>>> ObjectTypeConf and checks the maintainTms boolean there, instead of the >>>>> current engine scoped configuration. When a logical insertion occurs and the >>>>> ObjectTypeConf is retrieved if maintainTms is false it sets the value to >>>>> true and then iterates the associated ObjectTypeNode memory lazily adding >>>>> all the objects to the TMS equality map. From then on for that ObjectType >>>>> all inserted objects are added to that equality map. >>>>> >>>>> With this you now have the advantage of TMS being laziy enabled, so >>>>> the minor hashmap operation is no longer used and likewise a small memory >>>>> saving from not populating the map. There is a further advantage that this >>>>> is now fine grained and when enabled only impacts for that specific object >>>>> type. >>>>> >>>>> A further enhancement could use a int counter, instead of a boolean. >>>>> Each logical insertion for that object type increases the counter, each >>>>> retraction decreases the counter; even if automatically retracted if the >>>>> truth is broken for that logical assertion. When the counter reaches zero, >>>>> TMS for that OTN can be disabled. We do not however remove the objects from >>>>> the equality map, as this would cause "churn" if TMS is continuously enabled >>>>> and disabled. Instead when TMS is disabled record the current fact counter >>>>> id. Then if TMS is disabled on a retraction but there is a counter id, we >>>>> can check that counter id to see if the fact is prior to TMS being disabled >>>>> and thus would need to be retracted from the equality map. >>>>> >>>>> _______________________________________________ >>>>> rules-dev mailing list >>>>> rules-dev(a)lists.jboss.org >>>>> https://lists.jboss.org/mailman/listinfo/rules-dev >>>>> >>>>> >>>> >>>> _______________________________________________ >>>> rules-dev mailing listrules-dev@lists.jboss.orghttps://lists.jboss.org/mailman/listinfo/rules-dev >>>> >>>> >>>> >>>> _______________________________________________ >>>> rules-dev mailing list >>>> rules-dev(a)lists.jboss.org >>>> https://lists.jboss.org/mailman/listinfo/rules-dev >>>> >>>> >>> >> >> > > > _______________________________________________ > rules-dev mailing list > rules-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-dev > > -- - CTO @ http://www.plugtree.com - MyJourney @ http://salaboy.wordpress.com - Co-Founder @ http://www.jbug.com.ar - Salatino "Salaboy" Mauricio - _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev