On 2012-10-13 01:26, Sean Kelly wrote:
Here are my results:
$ dmd -release -inline -O dtest
$ ll input.txt
-rw-r--r-- 1 sean staff 365105313 Oct 12 15:50 input.txt
$ time dtest
real 1m36.462s
user 1m32.468s
sys 0m1.102s
Then I ran my SAX style parser example on the same input file:
$ make example
cc example.c -o example lib/release/myparser.a
$ time example
real 0m2.191s
user 0m1.944s
sys 0m0.241s
So clearly the problem isn't parsing JSON in general but rather generating an
object tree for a large input stream. Note that the D app used gigabytes of
memory to process this file--I believe the total VM footprint was around 3.5
GB--while my app used a fixed amount roughly equal to the size of the input
file. In short, DOM style parsers are great for small data and terrible for
large data.
I tried JSON parser in Tango, using D2, this is the results I got for a
file just below 360 MB:
real 1m2.848s
user 0m58.321s
sys 0m1.423s
Since the XML parser in Tango is so fast I expected more from the JSON
parser as well. But I have no idea what kind of parser the JSON parser uses.
--
/Jacob Carlborg
