mina-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Goldstein Lyor (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (SSHD-854) Massive object graph in NioSocketSession
Date Sun, 28 Oct 2018 05:22:00 GMT

    [ https://issues.apache.org/jira/browse/SSHD-854?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16666290#comment-16666290
] 

Goldstein Lyor commented on SSHD-854:
-------------------------------------

{quote}
Clearly, the sessionClosed() method from the CachingPublicKeyAuthenticator class is not being
called,
{quote}
As far as I can tell from looking at the code, {{sessionClosed}} is always called since it
is part of the {{preClose}} sequence - which is part of any {{Closeable#close}}.

That being said, I am not able to see the benefits of this class - why would we want to cache
the authentication result per-session ? After all, once the session is authenticated, the
verifier is not consulted again (for the same session).

> Massive object graph in NioSocketSession
> ----------------------------------------
>
>                 Key: SSHD-854
>                 URL: https://issues.apache.org/jira/browse/SSHD-854
>             Project: MINA SSHD
>          Issue Type: Bug
>            Reporter: jpalacios
>            Priority: Major
>
> I'm looking at a heap dump from one of our customers where the retained heap size for
some {{NioSocketSession}} instances is almost 1GB.
> From the looks of the dump MINA has created a massive object graph where:
> {code}
> NioSocketSession -> SelectionKeyImpl -> EpollSelectorImpl -> HashMap -> SelectionKeyImpl
-> NioSocketSession -> ...
> {code}
> From the looks of the obeject IDs these are not loops
> Each individual object is not large by itself but at the top of the graph the accumulated
retained size is enough to produce an OOME
> Could you help me understand how MINA can produce such a massive object graph? Should
MINA apply any defense mechanism to prevent this??



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Mime
View raw message