Sorry to resurrect a dead thread, but I figured it out: https://github.com/elasticsearch/elasticsearch/issues/5086
High level: 1. Hit ~1 million documents with a script score. 2. Do something like (doc['foo'].empty ? 0 : doc['foo'].value) * doc['bar']. The .empty is the key here. 3. If most of the documents don't have a foo then this is really slow. Like, two seconds slow. 4. Instead, switch to this (doc['foo'].isEmpty() ? 0 : doc['foo'].value) * doc['bar']. That is faster. .36 seconds or so. Not super speedy, but much better. On Wed, Jan 8, 2014 at 10:44 AM, Nikolas Everett <nik9...@gmail.com> wrote: > Does anyone know what might be causing MVEL to do this: > 100.3% (501.3ms out of 500ms) cpu usage by thread > 'elasticsearch[elastic1002][search][T#23]' > 9/10 snapshots sharing following 47 elements > java.lang.Throwable.fillInStackTrace(Native Method) > java.lang.Throwable.fillInStackTrace(Throwable.java:782) > java.lang.Throwable.<init>(Throwable.java:265) > java.lang.Exception.<init>(Exception.java:66) > java.lang.RuntimeException.<init>(RuntimeException.java:62) > > java.lang.IllegalArgumentException.<init>(IllegalArgumentException.java:53) > sun.reflect.GeneratedMethodAccessor45.invoke(Unknown Source) > > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) > java.lang.reflect.Method.invoke(Method.java:606) > > org.elasticsearch.common.mvel2.optimizers.impl.refl.nodes.GetterAccessor.getValue(GetterAccessor.java:43) > > org.elasticsearch.common.mvel2.optimizers.impl.refl.nodes.MapAccessorNest.getValue(MapAccessorNest.java:54) > > org.elasticsearch.common.mvel2.optimizers.impl.refl.nodes.VariableAccessor.getValue(VariableAccessor.java:37) > > org.elasticsearch.common.mvel2.ast.ASTNode.getReducedValueAccelerated(ASTNode.java:108) > > org.elasticsearch.common.mvel2.MVELRuntime.execute(MVELRuntime.java:86) > > org.elasticsearch.common.mvel2.compiler.CompiledExpression.getDirectValue(CompiledExpression.java:123) > > org.elasticsearch.common.mvel2.compiler.CompiledExpression.getValue(CompiledExpression.java:119) > > org.elasticsearch.common.mvel2.compiler.CompiledExpression.getValue(CompiledExpression.java:106) > > org.elasticsearch.common.mvel2.ast.Substatement.getReducedValueAccelerated(Substatement.java:44) > > org.elasticsearch.common.mvel2.ast.BinaryOperation.getReducedValueAccelerated(BinaryOperation.java:114) > > org.elasticsearch.common.mvel2.ast.BinaryOperation.getReducedValueAccelerated(BinaryOperation.java:114) > > org.elasticsearch.common.mvel2.compiler.ExecutableAccessor.getValue(ExecutableAccessor.java:42) > > org.elasticsearch.common.mvel2.optimizers.impl.refl.nodes.MethodAccessor.executeAndCoerce(MethodAccessor.java:164) > > org.elasticsearch.common.mvel2.optimizers.impl.refl.nodes.MethodAccessor.getValue(MethodAccessor.java:73) > > org.elasticsearch.common.mvel2.ast.ASTNode.getReducedValueAccelerated(ASTNode.java:108) > > org.elasticsearch.common.mvel2.MVELRuntime.execute(MVELRuntime.java:86) > > org.elasticsearch.common.mvel2.compiler.CompiledExpression.getDirectValue(CompiledExpression.java:123) > > org.elasticsearch.common.mvel2.compiler.CompiledExpression.getValue(CompiledExpression.java:119) > > org.elasticsearch.script.mvel.MvelScriptEngineService$MvelSearchScript.run(MvelScriptEngineService.java:191) > > org.elasticsearch.script.mvel.MvelScriptEngineService$MvelSearchScript.runAsDouble(MvelScriptEngineService.java:206) > > org.elasticsearch.common.lucene.search.function.ScriptScoreFunction.score(ScriptScoreFunction.java:54) > > It isn't an error. Looking at MVEL's source it looks like it catches this > error and works around it by inspecting the function, casting the arguments > appropriately, and they retying. I imagine it'd be nice and fast if I > didn't get the types wrong but it works anyway which feels a bit trappy at > scale. > > I know this is caused by scoring tons of documents in a FunctionScore > which is a pretty strong argument for moving all FunctionScoring into a > rescore for protection but what in the world am I doing with MVEL to make > it do this? > > My candidate MVEL looks like this: > log10( ($doc['a'].empty ? 0 : $doc['a']) + ($doc['b'].empty ? 0 : > $doc['b']) + 2 ) > > > I'm trying to reproduce it with the debugger and Elasticsearch's tests but > I haven't had any luck yet so I'd love to hear if anyone else has seen this. > > Nik > -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to elasticsearch+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/CAPmjWd3WCWxjTuoZZzmwtqG29Ld1dOrmT0yr9kZHat%3D0rPsqPg%40mail.gmail.com. For more options, visit https://groups.google.com/groups/opt_out.
