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POSending a blob to a servlet through ajax
 

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    <p>EDIT: The whole problem turned out to be a network issue, but if you see any ideas on how I could optimize the process I'd still appreciate it.</p> <p>I am fairly new to Servlets and not far into my journey I have encountered a problem, one related to performance. I am trying to send a video file through the XHR object in my Google Chrome browser. The video file is stored in a Blob object. I use this function in my JavaScript script:</p> <pre><code>function upload(blob) { var xhr = new XMLHttpRequest(); xhr.open('POST', '/Test/Odbieracz', true); xhr.onload = function(e) { console.log("loaded"); }; xhr.onreadystatechange = function(){ console.log("state: " + xhr.readyState); }; // Listen to the upload progress. xhr.upload.onprogress = function(e) { console.log("uploading..."); }; xhr.setRequestHeader("Content-Type", "video/webm"); xhr.send(blob); } </code></pre> <p>It works well, because the Blob reaches the Servlet where I use this bit of code to process it:</p> <pre><code>byte[] buffer = new byte[16 * 1024]; InputStream input = request.getInputStream(); OutputStream output = new FileOutputStream("costam0.webm"); int bytesRead; while ((bytesRead = input.read(buffer)) != -1){ System.out.println(bytesRead); output.write(buffer, 0, bytesRead); } output.close(); input.close(); </code></pre> <p>It saves the file as well.</p> <p>The issue I do have is that it is very very slow, according to my calculations it can process about 42kB/s, which for a web service having to do with video files is extremely slow. I have been sitting here for hours trying to find a way to speed it up somehow, or to at least find the bottleneck, but unfortunately I have no idea where it might be.</p> <p>My suspicion is that the browser is causing the lag, I have used a different InputStream in my Servlet leading to a local file (the same one I'm trying to upload through XHR) and it had no issue processing it at all, took less than a second. The server is stationed on my localhost, so I don't think the network is lagging me much at all.</p> <p>If anyone had this issue before, I'd be grateful for any pointers.</p>
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