Regarding caching, using Class as the key is a problem that most loggers have. I'm curious to see how Log4j, slf4j, jcl, etc have addressed it. Being that there's no easily available ConcurrentWeakMap, I can see how this could be difficult.
Darren > On Jan 16, 2014, at 11:03 AM, Lukas Eder <[email protected]> wrote: > > Hi Darren, > > I had tried once more and in a different Mission Control tab, I could also > see that getAnnotation() is incredibly expensive. Much more than getMethods() > or anything else. I'll investigate this more in-depth soon. Further head > start on a sensible solution is still appreciated, though. > > Cheers > Lukas > > > 2014/1/15 Darren Shepherd <[email protected]> >> I've broken the environment where I tested this, so I'll probably get back >> to you tomorrow. The stack trace is a bit different. It is on the >> getAnnotation() call not the getMethods() call. I'm also using jdk1.7.0_45 >> just incase that matters. I'll see if there is some easy way that I can >> reproduce it too. >> >> Darren >> >> >>> On Wed, Jan 15, 2014 at 10:41 AM, Lukas Eder <[email protected]> wrote: >>> Hi Darren, >>> Thanks for reporting this. I'll be tracking this issue as #2955 >>> https://github.com/jOOQ/jOOQ/issues/2955 >>> >>> Awesome news that Oracle now ships Mission Control with the JDK 7u40+. Just >>> about when I was going to renew my YourKit license :-) >>> So let's see if I read this correctly. The only significant contention I >>> get from the jOOQ integration tests originate from the benchmarks for the >>> into() method: >>> >>> <image.png> >>> >>> (disregard the AbstractLifecycleListener.testMethod()). Does the above >>> stack trace match your experience? Or is this really on the getAnnotation() >>> calls? Could you please provide me with a screenshot from your side? Is >>> there a way to reproduce this issue easily? >>> >>> Note, if you're using the generated record classes, you may prefer using >>> this method: >>> - >>> http://www.jooq.org/javadoc/3.2.x/org/jooq/Record.html#into(org.jooq.Table) >>> >>> Over this one: >>> - >>> http://www.jooq.org/javadoc/3.2.x/org/jooq/Record.html#into(java.lang.Class) >>> >>> If you want to implement a cache, you may need to resort to implementing >>> your own RecordMapperProvider: >>> http://www.jooq.org/doc/3.2/manual/sql-execution/fetching/pojos-with-recordmapper-provider/ >>> >>> ... and have that RecordMapperProvider manage a Map<Class<?>, >>> DefaultRecordMapper>, which returns a previously initialised >>> DefaultRecordMapper when the same Class key is encountered. The reason this >>> wasn't implemented in jOOQ is because caches that use Class keys need to >>> properly hook into ClassLoader mechanisms in order to invalidate >>> themselves. In those discussions, we didn't come to a satisfactory solution. >>> >>> Cheers >>> Lukas >>> >>> 2014/1/15 Darren S <[email protected]> >>>> Hi Lukas, >>>> >>>> I was performance testing my application and surprisingly found the JPA >>>> annotation support in jOOQ to be a pretty significant bottleneck. The >>>> test I'm doing is essentially a significant amount of "get by id" and >>>> "update by id," a couple hundred threads in parallel. So the SQL is super >>>> simple. I'm looking for some guidance on what is the best route forward. >>>> I had once asked about caching the reflection information in the default >>>> mapper and I believe you said there was some option or it wasn't cached by >>>> default. Regardless, here's the details. >>>> >>>> I highly recommend running Java Mission Control to reproduce this. Its >>>> freely available and packaged by default in the latest Java 7 JDKs. If >>>> you run it, look in the threads section for "contention." Basically what >>>> I'm seeing is that in a 60 second sample, over 30s is waiting on a lock >>>> held while the JDK is parsing the annotations. Because I have a high >>>> degree of concurrency on a small amount of tables (record classes) this >>>> leads to a significant amount of blocking. Basically, everytime you list >>>> the methods of a class, you actually get a new list with new Method >>>> instances. So when you call getAnnotation() it seems to actually parse >>>> the class bytes (or something). Then it caches the result in the Method >>>> obj. But if you get the method object over and over again, the caching is >>>> defeated. >>>> >>>> I disabled JPA by just changing the code and having isJPAenabled() return >>>> false. That sped up my application by almost 10x. I can't actually get >>>> rid of the JPA, I need the annotations. But I don't need JPA for the >>>> jOOQ mapper specifically. Specifically, I need jOOQ to generate the JPA >>>> annotations on the objects so that other programs can read the metadata, >>>> but at runtime I'm just using the generated record classes, so the JPA >>>> information is not needed by jOOQ. So is there some option to turn on >>>> caching or do I need to implemented a custom mapping provider? >>>> >>>> Thanks, >>>> Darren >>>> -- >>>> You received this message because you are subscribed to the Google Groups >>>> "jOOQ User Group" group. >>>> To unsubscribe from this group and stop receiving emails from it, send an >>>> email to [email protected]. >>>> >>>> For more options, visit https://groups.google.com/groups/opt_out. >>> >>> -- >>> You received this message because you are subscribed to a topic in the >>> Google Groups "jOOQ User Group" group. >>> To unsubscribe from this topic, visit >>> https://groups.google.com/d/topic/jooq-user/YpIpRVVsd5A/unsubscribe. >>> To unsubscribe from this group and all its topics, send an email to >>> [email protected]. >>> >>> For more options, visit https://groups.google.com/groups/opt_out. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "jOOQ User Group" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/groups/opt_out. > > -- > You received this message because you are subscribed to a topic in the Google > Groups "jOOQ User Group" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/jooq-user/YpIpRVVsd5A/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. -- You received this message because you are subscribed to the Google Groups "jOOQ User Group" group. 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