ignite-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "ASF GitHub Bot (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (IGNITE-4477) Fix IgniteFuture.listen() and IgniteFuture.chain() semantics
Date Thu, 20 Apr 2017 15:04:04 GMT

    [ https://issues.apache.org/jira/browse/IGNITE-4477?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15976852#comment-15976852
] 

ASF GitHub Bot commented on IGNITE-4477:
----------------------------------------

GitHub user dkarachentsev opened a pull request:

    https://github.com/apache/ignite/pull/1844

    IGNITE-4477 - Fix IgniteFuture.listen() and IgniteFuture.chain() semantics

    

You can merge this pull request into a Git repository by running:

    $ git pull https://github.com/gridgain/apache-ignite ignite-4477-1

Alternatively you can review and apply these changes as the patch at:

    https://github.com/apache/ignite/pull/1844.patch

To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:

    This closes #1844
    
----

----


> Fix IgniteFuture.listen() and IgniteFuture.chain() semantics
> ------------------------------------------------------------
>
>                 Key: IGNITE-4477
>                 URL: https://issues.apache.org/jira/browse/IGNITE-4477
>             Project: Ignite
>          Issue Type: Task
>          Components: general
>    Affects Versions: 1.8
>            Reporter: Vladimir Ozerov
>            Assignee: Dmitry Karachentsev
>              Labels: important
>             Fix For: 2.1
>
>
> *Problem*
> We allow users to pass continuations to {{IgniteFuture}} which will be executed on future
completion. This can be done through {{listen}} or {{chain}} methods.
> However, continuation semantics is broken intrinsically:
> 1) If future is already completed, user code executed in the same thread;
> 2) If future is not completed yet, it will be executed in completion thread.
> Neither of this options are valid because it easily leads to starvation. E.g.:
> {code}
> IgniteFuture fut = cache.getAsync(key2);
> fut.listen(fut0 -> {
>      cache.put(key2, val2); // Possible deadlock, because invoked in sys pool;
> });
> {code}
> *Solution*
> 1) By default callbacks must be executed asynchronously in some common pool (public pool?
new "callback pool"? FJP?)
> 2) It should be possible to specify where to execute a callback explicitly:
> {code}
> IgniteFuture.listen(IgniteClosure, ExecutorService);
> {code}
> 3) We may want to expose our public pool on API for convenience.



--
This message was sent by Atlassian JIRA
(v6.3.15#6346)

Mime
View raw message