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Re: Connection Pool monitoring data - spooky math?

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Shalini Guest
Offline
Joined: 2011-04-18

Please file an issue with all the steps and the connection pool
configuration.

On Thursday 01 November 2012 07:41 PM, Bryan Varner wrote:
> I'm in the process of migrating an existing system to glassfish 3.1.2.2
>
> At this point, we're trying to get the bean pool's & connection pools tuned appropriately for our apps.
>
> I've enabled high monitoring server-wide, and started running some normal usage pattern test cases on our servers.
>
> I'm accustomed to C3P0 connection pools, which are really easy to instrument and gauge your pool resource usage.
> With C3P0 the most pertinent data points we monitor when tuning the app are:
> numConnections (current pool size)
> numBusyConnections (number of connections currently in use)
> maxPoolSize (maximum size of pool)
> minPoolSize (min / steady pool size)
>
> It looks like the analogous values in GF monitoring would be:
> NumConnCreated - NumConnDestroyed = current pool size
> NumConnUsed = number of connections currently in use
>
> And then I could read the min / max off the pool's config.
>
> The problem that I have, is that the numbers I'm seeing in the GF monitoring data don't make sense!
>
> For instance, right now I have NumConnFree = -3989, and NumConnUsed = 4000, on a pool that's configured with a maximum connection size of 75.
>
> How can the number of free connections in the pool be a _negative_ number, and how can NumConnUsed be so high?
>
> Am I reading the intent of these metrics incorrectly because I'm expecting to be able to see the current state of the pool rather than just hit counters?
>
> Help!?
>
> Regards,
> - Bryan Varner

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Bryan Varner

So I'm not reading this wrong, and the numbers I'm seeing do not make sense?
________________________________________
From: Shalini [shalini.muthukrishnan...]
Sent: Sunday, November 04, 2012 11:30 PM
To: users@glassfish.java.net
Subject: Re: Connection Pool monitoring data - spooky math?

Please file an issue with all the steps and the connection pool
configuration.

On Thursday 01 November 2012 07:41 PM, Bryan Varner wrote:
> I'm in the process of migrating an existing system to glassfish 3.1.2.2
>
> At this point, we're trying to get the bean pool's & connection pools tuned appropriately for our apps.
>
> I've enabled high monitoring server-wide, and started running some normal usage pattern test cases on our servers.
>
> I'm accustomed to C3P0 connection pools, which are really easy to instrument and gauge your pool resource usage.
> With C3P0 the most pertinent data points we monitor when tuning the app are:
> numConnections (current pool size)
> numBusyConnections (number of connections currently in use)
> maxPoolSize (maximum size of pool)
> minPoolSize (min / steady pool size)
>
> It looks like the analogous values in GF monitoring would be:
> NumConnCreated - NumConnDestroyed = current pool size
> NumConnUsed = number of connections currently in use
>
> And then I could read the min / max off the pool's config.
>
> The problem that I have, is that the numbers I'm seeing in the GF monitoring data don't make sense!
>
> For instance, right now I have NumConnFree = -3989, and NumConnUsed = 4000, on a pool that's configured with a maximum connection size of 75.
>
> How can the number of free connections in the pool be a _negative_ number, and how can NumConnUsed be so high?
>
> Am I reading the intent of these metrics incorrectly because I'm expecting to be able to see the current state of the pool rather than just hit counters?
>
> Help!?
>
> Regards,
> - Bryan Varner

jsl123
Offline
Joined: 2006-07-20

You're not going mad, I've noticed the same problems, I've currently got
-180 free connections. The created and freed counts look to be accurate,
so I'd use those in the mean time and take the difference

John

On 05/11/2012 14:11, Bryan Varner wrote:
> So I'm not reading this wrong, and the numbers I'm seeing do not make sense?
> ________________________________________
> From: Shalini [shalini.muthukrishnan...]
> Sent: Sunday, November 04, 2012 11:30 PM
> To: users@glassfish.java.net
> Subject: Re: Connection Pool monitoring data - spooky math?
>
> Please file an issue with all the steps and the connection pool
> configuration.
>
> On Thursday 01 November 2012 07:41 PM, Bryan Varner wrote:
>> I'm in the process of migrating an existing system to glassfish 3.1.2.2
>>
>> At this point, we're trying to get the bean pool's & connection pools tuned appropriately for our apps.
>>
>> I've enabled high monitoring server-wide, and started running some normal usage pattern test cases on our servers.
>>
>> I'm accustomed to C3P0 connection pools, which are really easy to instrument and gauge your pool resource usage.
>> With C3P0 the most pertinent data points we monitor when tuning the app are:
>> numConnections (current pool size)
>> numBusyConnections (number of connections currently in use)
>> maxPoolSize (maximum size of pool)
>> minPoolSize (min / steady pool size)
>>
>> It looks like the analogous values in GF monitoring would be:
>> NumConnCreated - NumConnDestroyed =urrent pool size
>> NumConnUsed =umber of connections currently in use
>>
>> And then I could read the min / max off the pool's config.
>>
>> The problem that I have, is that the numbers I'm seeing in the GF monitoring data don't make sense!
>>
>> For instance, right now I have NumConnFree =3989, and NumConnUsed = 4000, on a pool that's configured with a maximum connection size of 75.
>>
>> How can the number of free connections in the pool be a _negative_ number, and how can NumConnUsed be so high?
>>
>> Am I reading the intent of these metrics incorrectly because I'm expecting to be able to see the current state of the pool rather than just hit counters?
>>
>> Help!?
>>
>> Regards,
>> - Bryan Varner

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Bryan Varner

Thanks for the response, John.

Our app isn't anything trivial, and taking the time to try and code up a test app that will expose the issue is going to take me time I don't really have.

I'm glad to know I'm not the only one seeing it.

-Bryan
________________________________________
From: John Lister [john.lister@kickstone.com]
Sent: Tuesday, November 06, 2012 6:16 AM
To: users@glassfish.java.net
Subject: Re: RE: Connection Pool monitoring data - spooky math?

You're not going mad, I've noticed the same problems, I've currently got
-180 free connections. The created and freed counts look to be accurate,
so I'd use those in the mean time and take the difference

John

On 05/11/2012 14:11, Bryan Varner wrote:
> So I'm not reading this wrong, and the numbers I'm seeing do not make sense?
> ________________________________________
> From: Shalini [shalini.muthukrishnan...]
> Sent: Sunday, November 04, 2012 11:30 PM
> To: users@glassfish.java.net
> Subject: Re: Connection Pool monitoring data - spooky math?
>
> Please file an issue with all the steps and the connection pool
> configuration.
>
> On Thursday 01 November 2012 07:41 PM, Bryan Varner wrote:
>> I'm in the process of migrating an existing system to glassfish 3.1.2.2
>>
>> At this point, we're trying to get the bean pool's & connection pools tuned appropriately for our apps.
>>
>> I've enabled high monitoring server-wide, and started running some normal usage pattern test cases on our servers.
>>
>> I'm accustomed to C3P0 connection pools, which are really easy to instrument and gauge your pool resource usage.
>> With C3P0 the most pertinent data points we monitor when tuning the app are:
>> numConnections (current pool size)
>> numBusyConnections (number of connections currently in use)
>> maxPoolSize (maximum size of pool)
>> minPoolSize (min / steady pool size)
>>
>> It looks like the analogous values in GF monitoring would be:
>> NumConnCreated - NumConnDestroyed =urrent pool size
>> NumConnUsed =umber of connections currently in use
>>
>> And then I could read the min / max off the pool's config.
>>
>> The problem that I have, is that the numbers I'm seeing in the GF monitoring data don't make sense!
>>
>> For instance, right now I have NumConnFree =3989, and NumConnUsed = 4000, on a pool that's configured with a maximum connection size of 75.
>>
>> How can the number of free connections in the pool be a _negative_ number, and how can NumConnUsed be so high?
>>
>> Am I reading the intent of these metrics incorrectly because I'm expecting to be able to see the current state of the pool rather than just hit counters?
>>
>> Help!?
>>
>> Regards,
>> - Bryan Varner

--
Get the PriceGoblin Browser Addon
www.pricegoblin.co.uk

Shalini Guest
Offline
Joined: 2011-04-18

There could be some issue, yes, the numbers don't look right to me.
Please file an issue with all the details.
On Monday 05 November 2012 07:41 PM, Bryan Varner wrote:
> So I'm not reading this wrong, and the numbers I'm seeing do not make sense?
> ________________________________________
> From: Shalini [shalini.muthukrishnan...]
> Sent: Sunday, November 04, 2012 11:30 PM
> To: users@glassfish.java.net
> Subject: Re: Connection Pool monitoring data - spooky math?
>
> Please file an issue with all the steps and the connection pool
> configuration.
>
> On Thursday 01 November 2012 07:41 PM, Bryan Varner wrote:
>> I'm in the process of migrating an existing system to glassfish 3.1.2.2
>>
>> At this point, we're trying to get the bean pool's & connection pools tuned appropriately for our apps.
>>
>> I've enabled high monitoring server-wide, and started running some normal usage pattern test cases on our servers.
>>
>> I'm accustomed to C3P0 connection pools, which are really easy to instrument and gauge your pool resource usage.
>> With C3P0 the most pertinent data points we monitor when tuning the app are:
>> numConnections (current pool size)
>> numBusyConnections (number of connections currently in use)
>> maxPoolSize (maximum size of pool)
>> minPoolSize (min / steady pool size)
>>
>> It looks like the analogous values in GF monitoring would be:
>> NumConnCreated - NumConnDestroyed = current pool size
>> NumConnUsed = number of connections currently in use
>>
>> And then I could read the min / max off the pool's config.
>>
>> The problem that I have, is that the numbers I'm seeing in the GF monitoring data don't make sense!
>>
>> For instance, right now I have NumConnFree = -3989, and NumConnUsed = 4000, on a pool that's configured with a maximum connection size of 75.
>>
>> How can the number of free connections in the pool be a _negative_ number, and how can NumConnUsed be so high?
>>
>> Am I reading the intent of these metrics incorrectly because I'm expecting to be able to see the current state of the pool rather than just hit counters?
>>
>> Help!?
>>
>> Regards,
>> - Bryan Varner