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https://issues.apache.org/jira/browse/COUCHDB-798?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Jan Lehnardt closed COUCHDB-798.
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    Resolution: Fixed

> Compile mochijson2 down to native code
> --------------------------------------
>
>                 Key: COUCHDB-798
>                 URL: https://issues.apache.org/jira/browse/COUCHDB-798
>             Project: CouchDB
>          Issue Type: Improvement
>          Components: Database Core
>            Reporter: Adam Kocoloski
>             Fix For: 1.2
>
>
> Adding a -compile(native) flag to mochijson2.erl results in a marked 
> performance improvement for large documents.  I did the following test
> node compare_write.js -u http://127.0.0.1:5984 -v http://127.0.0.1:5985 -1 
> trunk -2 mochijson2-native -d large -r 2 -t 90 -c 200
> and got the results at [1].  The graph shows that the average client response 
> time dropped by about 35% with the native encoder.  Qualitatively, I also 
> noticed that the native encoder used substantially fewer CPU cycles.  On my 
> dual core Macbook, idle CPU went from ~10% on trunk to ~25% with the +native 
> version while the test was running.
> Running the same test with small documents showed essentially no difference 
> between the two comparatives, which is not surprising.
> A potential downside of +native is instability in the VM.  I've encountered 
> issues on AMD machines with R13B04 when using +native for all modules, and 
> the core dump pointed to an issue in HiPE.  On the other hand, I think that 
> mochijson2 should work very well as native code, since it doesn't do any 
> message passing or I/O.  I'm +1 on simply adding the compile option to the 
> codebase in trunk to see how it behaves.
> [1]: 
> http://mikeal.couchone.com/graphs/_design/app/_show/compareWriteTest/e69057a29bd6e4ac4ae0115fac00ae50

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