Mailing-List: contact hdfs-issues-help@hadoop.apache.org; run by ezmlm
Precedence: bulk
Date: Sat, 18 Nov 2017 05:05:00 +0000 (UTC)
From: "Mukul Kumar Singh (JIRA)" <jira@apache.org>
To: hdfs-issues@hadoop.apache.org
Message-ID: <JIRA.13118355.1510691757000.272570.1510981500114@Atlassian.JIRA>
In-Reply-To: <JIRA.13118355.1510691757000@Atlassian.JIRA>
References: <JIRA.13118355.1510691757000@Atlassian.JIRA> <JIRA.13118355.1510691757787@jira-lw-us.apache.org>
Subject: [jira] [Commented] (HDFS-12813) RequestHedgingProxyProvider can
 hide Exception thrown from the Namenode for proxy size of 1
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
archived-at: Sat, 18 Nov 2017 05:05:05 -0000


    [ https://issues.apache.org/jira/browse/HDFS-12813?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16257924#comment-16257924 ] 

Mukul Kumar Singh commented on HDFS-12813:
------------------------------------------


    Let's have two unwrap methods to handle two different cases
        ExecutionException(InvocationTargetExeption(SomeException))
        InvocationTargetException(SomeException)
bq. Done

    Also, the parameter of these two methods should be ExecutionException or InvocationTargetException instead of Exception.
bq. Done

    Pass the unwrapped exception to logProxyException. Then, isStandbyException does not need to unwrap it again.
bq. Done

    Question: It seems to me that the code expects either ExecutionException or InvocationTargetException, could we catch either ExecutionException or InvocationTargetException instead of Exception?
bq. Done

    Question: the patch changes successfulProxy to lastUsedProxy. Then, getProxy() may return "last unsuccessful proxy". Is it okay?
bq. I looked into the code and figured that a proxy will be used for {{expectedFailoverCount}} in RetryInvocationHandler#failover before the currently used proxy is being rejected. So I feel it is fine that {{currentUsedProxy}} will be reused.


> RequestHedgingProxyProvider can hide Exception thrown from the Namenode for proxy size of 1
> -------------------------------------------------------------------------------------------
>
>                 Key: HDFS-12813
>                 URL: https://issues.apache.org/jira/browse/HDFS-12813
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: ha
>            Reporter: Mukul Kumar Singh
>            Assignee: Mukul Kumar Singh
>         Attachments: HDFS-12813.001.patch, HDFS-12813.002.patch, HDFS-12813.003.patch
>
>
> HDFS-11395 fixed the problem where the MultiException thrown by RequestHedgingProxyProvider was hidden. However when the target proxy size is 1, then unwrapping is not done for the InvocationTargetException. for target proxy size of 1, the unwrapping should be done till first level where as for multiple proxy size, it should be done at 2 levels.


--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscribe@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-help@hadoop.apache.org