Performance considerations of JSON vs. XML

Question

I am using a webservice which provides a large result set either in XML or JSON format. Which format will be faster or better (perfomance based)? Also which language should I use to parse the XML/JSON? Should I use PHP or JavaScript?

Answer 1

"PHP or JavaScript" sounds like an odd choice to offer: PHP is usually used as a server-side language, whereas JavaScript is usually used as a client-side language.

What's your situation? What makes you suggest those two languages in particular? If you could give more information about what you're trying to do, that would help a lot. (We don't know whether you're developing a web app, a batch processing tool, a GUI application, etc.)

I suspect JSON will be a bit more compact than XML, although if they're compressing the data you may well find they end up taking the same bandwith (as a lot of the "bloat" of XML is easily compressible).

As ever, the best way to find out is to test the specific web service with some realistic data. Generalities aren't a good basis for decision-making.

Answer 2

both have their advantages:

JSON

• easy to handle: $dataStructure = JSON_decode($serializedString);, done.

XML

• partial data handling: if your result-set is too big to be processed (parsed) at once, this may be the way to go. note: SimpleXML is the easier to work with xml lib, but also parses the whole xml-file at once, so in this case there's no benefit over JSON.

the question which language to handle your result set with is a bit non-sensical. javascript is client-side*, php is server side. so, it depends on what you want to do with the result set.

you can pass the result directly on to the browser/js without doing anything on the server side, and let the client do the filtering and rendering. this may make sense in certain situations, but normally it's not what you want.

my advice: if possible, use JSON.

ad *: you can use javascript on the server side (rhino, v8cgi, ...), but that's not what you have in mind.