[
https://issues.apache.org/jira/browse/ZOOKEEPER-2770?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16100846#comment-16100846
]
Michael Han commented on ZOOKEEPER-2770:
----------------------------------------
A hardcoded default value in code is unlikely to work for everyone and it is
possible to have false negatives if the value is too small. I am leaning
towards have this feature as an opt-in feature with the value has its default
-1 only and for those who want use it they can tune the parameter for their
deployment but it has to be enabled explicitly.
> ZooKeeper slow operation log
> ----------------------------
>
> Key: ZOOKEEPER-2770
> URL: https://issues.apache.org/jira/browse/ZOOKEEPER-2770
> Project: ZooKeeper
> Issue Type: Improvement
> Reporter: Karan Mehta
> Assignee: Karan Mehta
> Attachments: ZOOKEEPER-2770.001.patch, ZOOKEEPER-2770.002.patch,
> ZOOKEEPER-2770.003.patch
>
>
> ZooKeeper is a complex distributed application. There are many reasons why
> any given read or write operation may become slow: a software bug, a protocol
> problem, a hardware issue with the commit log(s), a network issue. If the
> problem is constant it is trivial to come to an understanding of the cause.
> However in order to diagnose intermittent problems we often don't know where,
> or when, to begin looking. We need some sort of timestamped indication of the
> problem. Although ZooKeeper is not a datastore, it does persist data, and can
> suffer intermittent performance degradation, and should consider implementing
> a 'slow query' log, a feature very common to services which persist
> information on behalf of clients which may be sensitive to latency while
> waiting for confirmation of successful persistence.
> Log the client and request details if the server discovers, when finally
> processing the request, that the current time minus arrival time of the
> request is beyond a configured threshold.
> Look at the HBase {{responseTooSlow}} feature for inspiration.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
