Hello again, and thank you for all your replies. I will try to break them down in an organized fashion.
Kumar: The while loop takes <20ms on the emulator, and less still on the Nexus One. I have measured the time it takes for every line to complete -- I'm sorry I did not mention that. The problem is in the call to the web service (i.e. client.execute(request), or androidHttpTransport.call(soapAction, envelope) from another way of trying). I have much more code from me trying this many different ways; this is a single snapshot of where I left the code. Jason: I don't understand how the browser can be so much faster than a direct HTTP call to the web service. I do know that timing the execution synchronously is not going to give me perfect results, but I timed the timer and, especially on the Nexus One, it takes a negligible amount of time for the timer code to run. What I forgot to mention was that we have tried hosting the web service locally on our network (<1ms late...@100mbit) and even then the web service call takes >100ms through the app, and <20ms through the browser. This code is housed in WebService.java, which is always called asynchronously from other parts of the app. I wanted the entire instantiation to be asynchronous, in case in the future we decide to return or parse a more-than-trivial amount of data. I have ran this test with GZIP compression enabled and disabled. Unfortunately, it is not feasible to implement a local cache. That was my very first thought, but the data is important enough that I do not want the possibility of tech savvy users extracting the data themselves without using the web service the way it was intended. One thing I noticed, using Microsoft's Visual Round Trip Analyzer (very cool little tool, if you guys haven't used it already), is that a certain call to my .NET web service (which in this case returns a soap envelope with a .NET datatable inside, which I parse manually, blegh) results in a bunch of ACKs going back and forth. Over WiFi this isn't terrible, but over a higher latency connection like EDGE this takes 4+ seconds to complete. It looks like TCP Slow Start may have something to do with it, but admittedly I don't have enough knowledge of the inner workings of TCP to fix this issue. Here is what VRTA returns: KB Up=1.499 Down=8.765; Compressibility: 0.00; Packet Loss: 0.00% HTTPS NotSupported Headers (Size=0 Cookie=0): Response Status Code: null Headers (Size=0 Cookie=0): Time [ms]: TCP=86 TTFB=0 Total=2149 Frame ms A Size Proto Flags Communication 7 98 0 66 TCP .S Sync to establish Conn 8 184 86 66 TCP .S. .A <--- Sync-Ack confirm Conn 9 184 0 54 TCP ....A ---> Ack 10 405 220 142 TCP ...PA ---> Ack 11 499 95 1514 TCP ....A <--- Ack 12 502 3 1514 TCP ....A <--- Ack 13 502 0 54 TCP ....A ---> Ack 14 591 89 1159 TCP ...PA <--- Ack 15 795 203 54 TCP ....A ---> Ack 16 828 33 364 TCP ...PA ---> Ack 17 931 104 97 TCP ...PA <--- Ack 19 1137 205 54 TCP ....A ---> Ack 20 1903 767 286 TCP ...PA ---> Ack 21 2115 212 60 TCP ....A <--- Ack 22 2115 0 407 TCP ...PA ---> Ack 23 2247 132 1514 TCP ....A <--- Ack 24 2247 0 1514 TCP ....A <--- Ack 25 2247 0 1477 TCP ...PA <--- Ack 26 2247 0 60 TCP F.. .A <--- Close connection 27 2247 0 54 TCP ....A ---> Ack Are Android developers content with all calls to a web service taking 800ms over WiFi and 4000ms on EDGE? Again, thank you for all your replies. Regards, Adam Smith Norsoft On Nov 23, 9:33 am, Hal <[email protected]> wrote: > You may want to try Jt secure Web Services for Android: > > -Java Pattern Oriented Framework, An application of the Messaging > Design Pattern > IBM Technical > Libraryhttp://www.ibm.com/developerworks/webservices/library/ws-designpatter... > > - Messaging Design Pattern and a distributed Component/Service > Modelhttps://jt.dev.java.net/files/documents/5553/149793/MDPdistributedMod... > > The following code is taken from the Jt.JtURL component (invoked by > the Jt.rest.JtRestService component) > > private String doPost (String request) { > URLConnection urlConn; > URL destURL; > DataOutputStream outStream; > DataInputStream inStream; > int c; > StringBuffer sBuffer = new StringBuffer (); > > if (request == null) > return null; > > if (url == null) > return null; > > handleTrace ("request:" + request); > > try { > > destURL = new URL (url); > > urlConn = destURL.openConnection(); > urlConn.setDoOutput(true); > urlConn.setDoInput(true); > > urlConn.setRequestProperty("Content-length", > "" + request.length()); > > outStream = new DataOutputStream (urlConn.getOutputStream()); > > outStream.writeBytes(request); > > outStream.close (); > > inStream = new DataInputStream (urlConn.getInputStream()); > > while ((c = inStream.read()) >= 0) { > sBuffer.append((char) c); > } > } catch (Exception ex) { > handleException (ex); > } > > return ((String) sBuffer.toString()); > > } > > If feasible you may want to try without GZIP. It should be a bit > faster. > > On Nov 18, 6:00 pm, Wipeout <[email protected]> wrote: > > > > > > > > > Hey guys, > > This is my first post to the Android Developers group. I have been > > working with HTTP communication in the Android SDK and have noticed > > that calls to a web service through my app are very slow (taking > > 800+ms on high speed wifi). They take less than 100ms if I call the > > web service through the phone's browser. I am developing on a Google > > Nexus One. The size of the data returned is very small, <1K. I have > > tried enabling gzip compression, and that helps slightly but I assume > > there is another problem at hand. I have tried using SOAP with the > > ksoap2-android library, as well as making things simple using > > HttpClient and InputStreamReader. Below is my code for the fastest I > > can make the app perform; using no SOAP, and using GZIP compression. I > > apologize for the lengthy code -- I think all of it is beneficial for > > determining the best way to make this request and response happen > > faster. > > > [code] > > public String GetRest() > > { > > > long startTime = System.currentTimeMillis(); > > String result = ""; > > > Log.v("time", "Beginning rest: " + (System.currentTimeMillis() - > > startTime) + "ms"); > > > try > > { > > HttpClient client = new DefaultHttpClient(); > > HttpGet request = new HttpGet("https://usad.enlyght.com/ws/ > > AndroidService.asmx/GetWebServiceVersion"); > > request.addHeader("Accept-Encoding", "gzip"); > > > Log.v("time", "Before call: " + (System.currentTimeMillis() > > - > > startTime) + "ms"); > > HttpResponse response = client.execute(request); > > InputStream instream = response.getEntity().getContent(); > > Header contentEncoding = response.getFirstHeader("Content- > > Encoding"); > > if (contentEncoding != null && > > contentEncoding.getValue().equalsIgnoreCase("gzip")) { > > instream = new GZIPInputStream(instream); > > } > > InputStreamReader isreader = new > > InputStreamReader(instream); > > BufferedReader reader = new BufferedReader(isreader); > > StringWriter sw = new StringWriter(); > > > String read; > > while ((read = reader.readLine()) != null) { > > result += read; > > } > > > client.getConnectionManager().shutdown(); > > } > > catch (Exception e) {} > > Log.v("time", "End rest: " + (System.currentTimeMillis() - > > startTime) + "ms"); > > > return result; > > } > > [/code] > > > Regards, > > Adam Smith > > Norsoft -- You received this message because you are subscribed to the Google Groups "Android Developers" group. 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