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Date: Fri, 18 Feb 2011 09:58:23 -0800
Message-ID: <AANLkTinxEDjb+b81pX03MGQ6EycGjLRm7avJmyb5aJSL@mail.gmail.com>
Subject: Re: Question about sharing Zookeeper connections
From: Benjamin Reed <ben.reed@gmail.com>
To: user@zookeeper.apache.org
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it does seem like a good idea to make multiple zk handles share a
connection, but as ted points out, they may have different timeouts, which
would make the sharing logic quite complicated. i think the implementation
might also be quite complicated. having said that, if someone could come up
with a simple and correct connection sharing implementation, we (or at least
i) would be open to it.

ben

On Fri, Feb 18, 2011 at 9:31 AM, Ted Dunning <ted.dunning@gmail.com> wrote:

> On Fri, Feb 18, 2011 at 1:24 AM, YUNG-LIN HO <yunglin@gmail.com> wrote:
>
> > Because zookeeper clients will try to keep session alive by sending a
> ping
> > request every 2 seconds. If libraries in an application do not share
> > connections with each other, they would flood the zookeeper server with
> > unnecessary requests and drag down performance of the server.
> >
>
> Make sure that you have a valid reason to worry first.
>
> Do you have thousands of clients?
>
> If not, these keep-alives are likely to be undetectable, load-wise.
>
>
> > I am wondering is there any connection manager exists in the
> > Hadoop/Zookeeper project that helps users to share connections?
> >
>
> Yes.  Zookeeper.
>
> Just open a single connection and pass it around via a singleton of some
> kind or your favorite dependency injection technique.
>
> This isn't always a great idea since your disconnect and expiration
> strategies might differ between different uses in important ways.
>

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