Github user karanmehta93 commented on a diff in the pull request:

    https://github.com/apache/zookeeper/pull/307#discussion_r128155180
  
    --- Diff: 
src/java/test/org/apache/zookeeper/server/ZooKeeperServerMainTest.java ---
    @@ -138,14 +145,56 @@ void delete(File f) throws IOException {
             ServerCnxnFactory getCnxnFactory() {
                 return main.getCnxnFactory();
             }
    +
         }
     
    -    public static  class TestZKSMain extends ZooKeeperServerMain {
    +    public static class TestZKSMain extends ZooKeeperServerMain {
    +
    +        private ServerStats serverStats;
    +
    +        @Override
    +        public ZooKeeperServer getZooKeeperServer(FileTxnSnapLog txnLog, 
ServerConfig config, ZKDatabase zkDb) {
    +            ZooKeeperServer zooKeeperServer = 
super.getZooKeeperServer(txnLog, config, zkDb);
    +            serverStats = zooKeeperServer.serverStats();
    +            return zooKeeperServer;
    +        }
    +
    +        @Override
             public void shutdown() {
                 super.shutdown();
             }
         }
     
    +    // Test for ZOOKEEPER-2770 ZooKeeper slow operation log
    +    @Test
    +    public void testRequestWarningThreshold() throws IOException, 
KeeperException, InterruptedException {
    +        ClientBase.setupTestEnv();
    +
    +        final int CLIENT_PORT = PortAssignment.unique();
    +
    +        MainThread main = new MainThread(CLIENT_PORT, true, null, 0);
    +        main.start();
    +
    +        Assert.assertTrue("waiting for server being up",
    +                ClientBase.waitForServerUp("127.0.0.1:" + CLIENT_PORT,
    +                        CONNECTION_TIMEOUT));
    +        // Get the stats object from the ZooKeeperServer to keep track of 
high latency requests.
    +        ServerStats stats = main.main.serverStats;
    +
    +        ZooKeeper zk = new ZooKeeper("127.0.0.1:" + CLIENT_PORT,
    +                ClientBase.CONNECTION_TIMEOUT, this);
    +
    +        zk.create("/foo1", "foobar".getBytes(), Ids.OPEN_ACL_UNSAFE,
    +                CreateMode.PERSISTENT);
    +
    +        Assert.assertEquals(new String(zk.getData("/foo1", null, null)), 
"foobar");
    +        // It takes a while for the counter to get updated sometimes, this 
is added to reduce flakyness
    +        Thread.sleep(1000);
    --- End diff --
    
    > We can always increase the counter before we send a response back to 
client in FinalRequestProcessor. This will make test deterministic, Or,
    
    Not this approach. It will boil down to the same thing as `ServerStats` 
which we don't want in the first place. 
    
    > In test, implement retry polling with a timeout and a smaller sleep 
interval (e..g 10ms instead of 1000ms). We use this pattern a lot in our test. 
In general we'd like to make deterministic tests as much as possible (in other 
words, avoid sleep at all cost.) though sometimes that is hard to do due to 
various reasons.
    
    I will add the polling mechanism with a smaller sleep interval. I would 
also love to make the test deterministic, however I don't think this will be 
possible here because of race condition involved between client side and server 
side processing thread.


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---

Reply via email to