如何提高多线程的性能

Question

我已经用谷歌搜索并找到了使用多线程的最佳方法，但它在 100 条记录中失败，它给出了 504 状态代码。是否有改进以下代码的余地？

@Scheduled(fixedRate = 5000)
public ResponseEntity<Object> getData(List<JSONObject> getQuoteJson, String username,
String authorization) throws ParseException, IOException, Exception {
HttpHeaders responseHeaders = new HttpHeaders();
responseHeaders.set("Access-Control-Allow-Origin", "*");
CompletableFuture<JSONArray> future = null;
JSONArray responseArray = new JSONArray();
try {
executor = Executors.newFixedThreadPool(getQuoteJson.size());
for (int i = 0; i < getQuoteJson.size(); i++) {
JSONObject jsonObject = (JSONObject) getQuoteJson.get(i);
future = CompletableFuture.supplyAsync(() -> {
JSONObject response = asynCallService.getDataAsyncService(jsonObject, productCode, authorization);
responseArray.add(response);
return responseArray;
}, executor);
}
return new ResponseEntity<Object>(future.get(), responseHeaders, HttpStatus.OK);
} catch (Exception e) {
throw e;
} finally {
executor.shutdown();
try {
executor.awaitTermination(Long.MAX_VALUE, TimeUnit.NANOSECONDS);
} catch (Exception e) {
}
}
}

Answer 1

不要每次都创建和关闭executor，请使用单一实例缓存线程池。由于重复创建线程是不必要的且昂贵的，线程池的好处是保持线程存在。

Answer 2

哇，所有这些都是为了只在列表上迭代异步？

我认为这更有可能是您搜索的内容：

HttpHeaders responseHeaders = new HttpHeaders();
responseHeaders.set("Access-Control-Allow-Origin", "*");
final JSONArray responseArray = new JSONArray();
getQuoteJson.parallelStream().map(e->asynCallService.getDataAsyncService(e, productCode, authorization)).forEach(responseArray::add);
return new ResponseEntity<Object>(responseArray, responseHeaders, HttpStatus.OK);