couchdb-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Filipe Manana (JIRA)" <j...@apache.org>
Subject [jira] [Created] (COUCHDB-1118) Adding a NIF based JSON decoding/encoding module
Date Sat, 02 Apr 2011 15:06:05 GMT
Adding a NIF based JSON decoding/encoding module
------------------------------------------------

                 Key: COUCHDB-1118
                 URL: https://issues.apache.org/jira/browse/COUCHDB-1118
             Project: CouchDB
          Issue Type: Improvement
          Components: Database Core
            Reporter: Filipe Manana
             Fix For: 1.2


Currently, all the Erlang based JSON encoders and decoders are very slow, and decoding and
encoding JSON is something that we do basically everywhere.

Via IRC, it recently discussed about adding a JSON NIF encoder/decoder. Damien also started
a thread at the development mailing list about adding NIFs to trunk.

The patch/branch at [1] adds such a JSON encoder/decoder. It is based on Paul Davis' eep0018
project [2]. Damien made some modifications [3] to it mostly to add support for big numbers
(Paul's eep0018 limits the precision to 32/64 bits) and a few optimizations. I made a few
corrections and minor enhancements on top of Damien's fork as well [4]. Finally BenoƮt identified
some missing capabilities compared to mochijson2 (on encoding, allow atoms as strings and
strings as object properties).

Also, the version added in the patch at [1] uses mochijson2 when the C NIF is not loaded.
Autotools configuration was adapted to compile the NIF only when we're using an OTP release
>= R13B04 (R13B03 NIF API is too limited and suffered many changes compared to R13B04 and
R14) - therefore it should work on any OTP release > R13B at least.

I successfully tested this on R13B03, R13B04 and R14B02 in an Ubuntu environment.
I'm not sure if it builds at all on Windows - would appreciate if someone could verify it.
Also, I'm far from being good with the autotools, so I probably missed something important
or I'm doing something in a not very standard way.

This NIF encoder/decoder is about one order of magnitude faster compared to mochijson2 and
other Erlang-only solutions such as jsx. A read and writes test with relaximation shows this
has a very positive impact, specially on reads (the EJSON encoding is more expensive than
JSON decoding) - http://graphs.mikeal.couchone.com/#/graph/698bf36b6c64dbd19aa2bef634052381

@Paul, since this is based on your eep0018 effort, do you think any other missing files should
be added (README, etap tests, etc)? Also, should we put somewhere a note this is based on
your project?

[1] - https://github.com/fdmanana/couchdb/compare/json_nif
[2] - https://github.com/davisp/eep0018
[3] - https://github.com/Damienkatz/eep0018/commits/master
[4] - https://github.com/fdmanana/eep0018/commits/final_damien

--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message