凌空慢，导致内存泄漏 [英] Volley slow and causing memory leak

问题描述

在我的项目，我使用抽射下载我分析，并显示在ListView一个JSON流。我用下面的方法加载我的数据：

In my project, I am using volley to download a JSON stream which I parse and show in a listview. I use the following method to load my data:

private void loadEventData(int year, final int month) {

    // get volley request queue
    requestQueue = cpcApplication.getRequestQueue(getActivity());

    String url = "****************?year=" + year
            + "&month=" + month;

    pd = ProgressDialog.show(getActivity(), "Loading Events", "Retrieving Data from Server");
    pd.setCancelable(true);

    JsonObjectRequest jr = new JsonObjectRequest(Request.Method.GET, url, null, new Response.Listener<JSONObject>() {

        @Override
        public void onResponse(JSONObject response) {

            Log.i(TAG, response.toString());

            // parse the incoming response
            parseJson(response, month);

            // notify the listview that the data set has changed
            adapter.notifyDataSetChanged();

            // set the listview at the top position
            listView.setSelection(current.get(Calendar.DAY_OF_MONTH));

            // dismiss the ProgressDialog
            pd.dismiss();

        }
        }, new Response.ErrorListener() {

        @Override
        public void onErrorResponse(VolleyError error) {

            error.printStackTrace();

            // cancel the progress dialog
            pd.dismiss();

            // let the user know that a network connection is not available
            Toast.makeText(getActivity(), "Cannot communicate with server.  Check network connection.", Toast.LENGTH_LONG).show();
        }

    });

    // add the network request to the queue
    requestQueue.add(jr);

}

这种方法的第一次调用精美的作品。在第二个电话，我得到一个超时错误。当我使用下面的命令：

The first call to this method works beautifully. In the second call, I get a timeout error. When I use the following command:

jr.setRetryPolicy(new DefaultRetryPolicy(
            2500, DefaultRetryPolicy.DEFAULT_TIMEOUT_MS, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));

要增加的时间量的要求，请求接管30秒，产生以下的日志输出：

to increase the amount of time for the request, the request takes over 30 seconds and produces the following log output:

10-19 20:53:19.746: D/Volley(17523): [2786] BasicNetwork.logSlowRequests: HTTP response for request=<[ ] http://************ 0x63ea5535 NORMAL 1> [lifetime=41769], [size=5467846], [rc=200], [retryCount=2]
10-19 20:53:19.796: D/dalvikvm(17523): GC_CONCURRENT freed 7462K, 26% free 24424K/33000K, paused 6ms+4ms, total 56ms
10-19 20:53:19.796: D/dalvikvm(17523): WAIT_FOR_CONCURRENT_GC blocked 51ms
10-19 20:53:19.826: I/dalvikvm-heap(17523): Grow heap (frag case) to 35.123MB for 10935708-byte allocation
10-19 20:53:19.857: D/dalvikvm(17523): GC_FOR_ALLOC freed 3K, 20% free 35100K/43680K, paused 23ms, total 28ms
10-19 20:53:19.917: D/dalvikvm(17523): GC_CONCURRENT freed 2018K, 19% free 35816K/43680K, paused 3ms+4ms, total 60ms
10-19 20:53:20.007: D/dalvikvm(17523): GC_CONCURRENT freed 4874K, 15% free 37226K/43680K, paused 2ms+3ms, total 27ms
10-19 20:53:20.007: D/dalvikvm(17523): WAIT_FOR_CONCURRENT_GC blocked 24ms
10-19 20:53:20.067: D/dalvikvm(17523): GC_FOR_ALLOC freed 5037K, 15% free 38601K/44900K, paused 19ms, total 19ms
10-19 20:53:20.117: D/dalvikvm(17523): GC_FOR_ALLOC freed 4680K, 14% free 40045K/46564K, paused 20ms, total 20ms
10-19 20:53:20.177: D/dalvikvm(17523): GC_FOR_ALLOC freed 5576K, 14% free 41572K/48272K, paused 20ms, total 20ms
10-19 20:53:20.227: D/dalvikvm(17523): GC_FOR_ALLOC freed 6133K, 15% free 43406K/50548K, paused 20ms, total 20ms
10-19 20:53:20.287: D/dalvikvm(17523): GC_CONCURRENT freed 6486K, 15% free 45029K/52428K, paused 2ms+2ms, total 24ms
10-19 20:53:20.287: D/dalvikvm(17523): WAIT_FOR_CONCURRENT_GC blocked 11ms
10-19 20:53:20.407: D/Volley(17523): [1] Request.finish: 42553 ms: [ ] http://****** 0x63ea5535 NORMAL 1

当我在浏览器中执行相同的请求，只需要几秒钟。为什么延迟和令人难以置信的内存消耗？

When I perform the same request in a browser, it takes only several seconds. Why the delay and incredible memory consumption?

推荐答案

的方法每次调用创建一个新的请求队列这不是一个推荐的方法。你应该创建一个请求队列，大概在创建应用程序时初始化一次公开可见单。

Every call to the method you create a new RequestQueue which is not a recommended approach. You should create one RequestQueue, probably a publicly visible singleton that is initialized once when the app is created.

尝试移动请求队列之外，看看它是否解决您的问题。

Try moving the RequestQueue outside and see if it solves your problem.

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