Обсуждение: Tomcat Connection Pool?

I am running a connection pool for the PostgreSQL and I was wondering which values you would reccommend for the connection pool?

                <parameter>
                        <name>maxWait</name>
                        <value>5000</value>
                </parameter>
                <parameter>
                        <name>maxActive</name>
                        <value>10</value>
                </parameter>
                <parameter>
                        <name>maxIdle</name>
                        <value>2</value>
                </parameter>

What does maxWait and maxIdle means?


Regards,

BTJ

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On 02/09/2003 23:06 Bjørn T Johansen wrote:
> I am running a connection pool for the PostgreSQL and I was wondering
> which values you would reccommend for the connection pool?
>
>                 <parameter>
>                         <name>maxWait</name>
>                         <value>5000</value>
>                 </parameter>
>                 <parameter>
>                         <name>maxActive</name>
>                         <value>10</value>
>                 </parameter>
>                 <parameter>
>                         <name>maxIdle</name>
>                         <value>2</value>
>                 </parameter>
>
> What does maxWait and maxIdle means?

maxWait is is maximum time the connection pool will wait for a connection
to become available so it only has an effect when all maxActive
connections are being used at the same time. maxIdle is the maximum number
of connections what the pool will keep open. Using your settings as an
example, say you reach a point where all 10 connections have beed created
and are in use and that sometime later the nunber of requests drops so
that they can serviced by just a few connections. In this case excess idle
connections will be closed but there will always be at least maxIdle
connections left open.
HTH

--
Paul Thomas
+------------------------------+---------------------------------------------+
| Thomas Micro Systems Limited | Software Solutions for the Smaller
Business |
| Computer Consultants         |
http://www.thomas-micro-systems-ltd.co.uk   |
+------------------------------+---------------------------------------------+

Oki, thx... Any ideas to what is sensible values also?
(Like number of maxIdle compared to maxActive, etc..)


BTJ

On Wed, 2003-09-03 at 15:34, Paul Thomas wrote:
> On 02/09/2003 23:06 Bjørn T Johansen wrote:
> > I am running a connection pool for the PostgreSQL and I was wondering
> > which values you would reccommend for the connection pool?
> >
> >                 <parameter>
> >                         <name>maxWait</name>
> >                         <value>5000</value>
> >                 </parameter>
> >                 <parameter>
> >                         <name>maxActive</name>
> >                         <value>10</value>
> >                 </parameter>
> >                 <parameter>
> >                         <name>maxIdle</name>
> >                         <value>2</value>
> >                 </parameter>
> >
> > What does maxWait and maxIdle means?
>
> maxWait is is maximum time the connection pool will wait for a connection
> to become available so it only has an effect when all maxActive
> connections are being used at the same time. maxIdle is the maximum number
> of connections what the pool will keep open. Using your settings as an
> example, say you reach a point where all 10 connections have beed created
> and are in use and that sometime later the nunber of requests drops so
> that they can serviced by just a few connections. In this case excess idle
> connections will be closed but there will always be at least maxIdle
> connections left open.
> HTH

On 03/09/2003 22:56 Bjørn T Johansen wrote:
> Oki, thx... Any ideas to what is sensible values also?
> (Like number of maxIdle compared to maxActive, etc..)
>

I think sensible values are going to be very dependent on the number of
requests. One way to find out might be to write a little utility to count
the number of back-end postgres connections and have it run every 3 or 4
seconds. That would give you an idea of the maximum and average number of
connections being used.

HTH

--
Paul Thomas
+------------------------------+---------------------------------------------+
| Thomas Micro Systems Limited | Software Solutions for the Smaller
Business |
| Computer Consultants         |
http://www.thomas-micro-systems-ltd.co.uk   |
+------------------------------+---------------------------------------------+

>
> On 03/09/2003 22:56 Bjørn T Johansen wrote:
>> Oki, thx... Any ideas to what is sensible values also?
>> (Like number of maxIdle compared to maxActive, etc..)
>>
>
> I think sensible values are going to be very dependent on the number of
> requests. One way to find out might be to write a little utility to count
> the number of back-end postgres connections and have it run every 3 or 4
> seconds. That would give you an idea of the maximum and average number of
> connections being used.
>
> HTH
>
> --
> Paul Thomas

Well, that's one way to go. Guess I just have to try and fail... :)
Thx....

BTJ