[infinispan-dev] Notifications for cache entry expired

[kapil nayar]

Hi Manik,

The purpose is the usual that the application would want to take some action
on expiry of the entry. Ofcourse the application can also start a timer in
parallel but those timers may again need to be synced up in case of
distributed apps.
However, your explanation brings out another question - is there an
additional overhead (memory related) using expiry on the cache entries as
compared to keeping an active control over the cache entry creation and
deletion. An application using only cache entries with expiry.

Thanks,
Kapil


>Date: Fri, 18 Jun 2010 22:44:59 +0100
>From: Manik Surtani <manik at jboss.org>
>Subject: Re: [infinispan-dev] Notifications for cache entry expired
>To: infinispan -Dev List <infinispan-dev at lists.jboss.org>
>Message-ID: <3EAE786D-FB0E-4217-AE4F-7D270B3A955F at jboss.org>
>Content-Type: text/plain; charset=us-ascii

>It is possible, yes, but it will never be very accurate since entries are
only tested for whether they are expired in one of several ways:

>1.  A user thread asks for the entry and it has expired.  It will then be
removed.
>2.  The entry is passivated/overflowed to disk and it has expired.  It will
again be removed.
>3.  An eviction maintenance thread kicks in and detects that it has
expired.  It will again be removed.

>So even if a notification is generated, it will not be generated at the
time the entry expired, but rather at the time Infinispan realises the entry
has expired (which may be later).

>Also, what is the purpose of this?  It does add quite a bit of overhead.

>Cheers
>Manik

>On 18 Jun 2010, at 18:07, kapil nayar wrote:

> Hi,
>
> I don't see the notification for cache entry expired.
>
> Is it on the roadmap / possible to support?
>
> Thanks,
> Kapil Nayar
>
> ______________________________
_________________
> infinispan-dev mailing list
> infinispan-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/infinispan-dev

>--
>Manik Surtani
>manik at jboss.org <manik at jboss.org>
>Lead, Infinispan
>Lead, JBoss Cache
>http://www.infinispan.org <http://www.infinispan.org/>
>http://www.jbosscache.org <http://www.jbosscache.org/>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/infinispan-dev/attachments/20100619/4e0f7b06/attachment.html