How can I make my android app receive/send data faster?

I have an app that needs to transfer data back and forth between a server, but the speed is not satisfactory right now. The main part is that I'm receiving and parsing JSON data (about 200 characters long) over 3g from a server, and the fastest it will ever do the task is about 5 seconds, but sometimes it will take long enough to timeout (upwards of 30 seconds). My server is a rackspace cloud server.

I thought I was following best practices, but it can't be so with these kinds of speeds. I am using AsyncTask and the same global HttpClient variable for everything.

Can you开发者_开发百科 help me find a better way?

I've thought about these options:

• using TCP instead of HTTP
• encoding the data to try to reduce the size (not sure how this would work)

I don't know a lot about TCP, but it seems like it would be less overhead. What would be the pros and cons of using TCP instead of HTTP? is it practical for a cell phone to do?

Thanks

fyi - once I solve the problem I'll accept an answer that's the most helpful. So far I've received some really great answers

EDIT: I made it so that I can see the progress as it downloads and I've noticed that it is staying at 0% for a long time then it is quickly going to 100% -- does anyone have any ideas in light of this new info? It may be relevant that I'm using a Samsung Epic with Froyo.

Try using GZIP to compress the data being sent. Note a code complete example, but it should get you on the right path.

Rejinderi is right; GSON rocks.

HttpGet getRequest = new HttpGet(url);
getRequest.addHeader("Accept-Encoding", "gzip");


InputStream instream = response.getEntity().getContent();
Header contentEncoding = response.getFirstHeader("Content-Encoding");
if (contentEncoding != null && contentEncoding.getValue().equalsIgnoreCase("gzip")) {
    instream = new GZIPInputStream(instream);
}

TCP is just HTTP at a lower level and if you really need performance then TCP is the one you should use. HTTP is easier to develop as there are more support and easier to implement as a developer it wraps a lot of things up so you don't have to implement them yourself. The overhead for your case shouldnt be that much.

As for the JSON data. check if its taking a long time, the normal JSON library java has is damn slow take a look here

http://www.cowtowncoder.com/blog/archives/2009/09/entry_326.html

Debug and see if that is the case. if its the json parse speed i suggest you use the gson library. Its cleaner and easy to implement and much MUCH faster.

Sounds like you need to profile the application to find out where your bottleneck is. You said you are sending data of about 200 chars. That is miniscule and I don't see how compression or anything strictly data related is going to make much of an impact on such a small data set.

I think it is more likely that you have some communication issues, perhaps attempting to establish a new connection for every transfer or something along those lines that is giving you all the overhead.

Profiling is the key to resolving your issues, anything else is a shot in the dark.