You are viewing a plain text version of this content. The canonical link for it is here.
Posted to users@tomcat.apache.org by Sai Kumar <sa...@gmail.com> on 2017/06/16 10:06:51 UTC

Connection pool issue was in with 7.0.52 version? And it is fixed in 7.0.78 version?

Hi ,

We are using following tomcat version
         Apache Tomcat/7.0.52
         Server number:  7.0.52.0
and currently we are facing a problem with this one.

We have an issue with connection pool. Actually we are using specific
connections but some how all the connections are utilized. If any new
request come then it is unable to fetch a connection because pool is empty.
But in real case there is no chance of using that much of connections
parallel. So as per our analysis following are our observations.
We are using max idle connections are 30 , but if we do the operations and
calculate the connections using Jconsle then IDLE connections are more than
30.
Please let us know is there any solution for this issue.
Please confirm the below points.
1.Is there any Connection pool issue in the 7.0.52 version?
2.And it is fixed in 7.0.78 version? Or else tell me in which version MY
CASE issue is fixed.


Thanks
-- 
S Saikumar

AW: Connection pool issue was in with 7.0.52 version? And it is fixed in 7.0.78 version?

Posted by "Kreuser, Peter" <pk...@airplus.com>.
Sai,

May I suggest that you update your production system and see if that helps? No matter if the problem is in the tomcat version or your software, Tomcat 7.0.52 is over three years old, and contains many security related problems. From the release notes I see also quite a few performance and stability related changes, so you may quite easily see changed behavior. (Plus the Bugzilla you mentioned - solved in 2014 in r1613137)

As Olaf said, your request is a pretty difficult question to be answered, as each of us needs to have a full memory of all changes to the connection pool and see a correlation to your problem. It would certainly be helpful to answer his questions so at least Olaf is able to find a way to help you. 

From my experience, connection pool issues - if they appear all of a sudden with new application releases and new functionality - are related to application handling of the connections, timeouts and error handling (eg. connection closing in finally blocks).

Kind regards

Peter


> Hi,
> Please let anyone confirm me that,Is there is any issue regarding the
> connection pool in Tomcat V7.0.52 or older  versions.
> And,In which version Connection pool Issue was resloved.
> 
> Thank you
> 
> On Mon, Jun 19, 2017 at 2:58 PM, Sai Kumar <sa...@gmail.com>
> wrote:
> 
> > Hi ,
> > Need one help.I just seen this.
> > *Bug 53367* <https://bz.apache.org/bugzilla/show_bug.cgi?id=53367> - Database
> > failure may cause pool to hang - in bugzilla.,
> > My problem is something related to this case.And the fix included two
> > files..
> > 1.FairBlockingQueue.java
> > 2.Bug53367.java
> > Can you please tell me .how to replace or deploy those files and test my
> > case.
> > I have no idea about it.So please tell me clearly.
> >
> > Thank you
> >
> > On Fri, Jun 16, 2017 at 5:39 PM, Olaf Kock <to...@olafkock.de> wrote:
> >
> >>
> >> Am 16.06.2017 um 14:00 schrieb Sai Kumar:
> >> > There is no problem with code,We are closing the connections properely.
> >> > This issue is occured in production side.We are highly suspecting that
> >> > there is an issue with the Tomcat server( V7.0.52). First of all,Please
> >> let
> >> > us know if there is any bug regarding the Connection pool in tomcat
> >> V7.0.52
> >> > .If yes,tell me which version to be use to eradicate this issue.
> >> > Again we are confirming that ,there is no problem with the code.
> >>
> >> This way we're back on my initial comment: "any bug regarding connection
> >> pool" is quite a broad question to ask.
> >>
> >> * How many /concurrent/ connections does your production server handle?
> >> * How many http handler (threads) did you configure on the machine that
> >> has the 4000 database connections?
> >> * How long are these connections leased from the pool on average / max?
> >> * Have you tried reproducing this in a minimal code environment?
> >>
> >> Olaf
> >>
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >> For additional commands, e-mail: users-help@tomcat.apache.org
> >>
> >>
> >
> >
> > --
> > S Saikumar
> >
> 
> 
> 
> -- 
> S Saikumar
>

---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org


Re: Connection pool issue was in with 7.0.52 version? And it is fixed in 7.0.78 version?

Posted by Sai Kumar <sa...@gmail.com>.
Hi,
Please let anyone confirm me that,Is there is any issue regarding the
connection pool in Tomcat V7.0.52 or older  versions.
And,In which version Connection pool Issue was resloved.

Thank you

On Mon, Jun 19, 2017 at 2:58 PM, Sai Kumar <sa...@gmail.com>
wrote:

> Hi ,
> Need one help.I just seen this.
> *Bug 53367* <https://bz.apache.org/bugzilla/show_bug.cgi?id=53367> - Database
> failure may cause pool to hang - in bugzilla.,
> My problem is something related to this case.And the fix included two
> files..
> 1.FairBlockingQueue.java
> 2.Bug53367.java
> Can you please tell me .how to replace or deploy those files and test my
> case.
> I have no idea about it.So please tell me clearly.
>
> Thank you
>
> On Fri, Jun 16, 2017 at 5:39 PM, Olaf Kock <to...@olafkock.de> wrote:
>
>>
>> Am 16.06.2017 um 14:00 schrieb Sai Kumar:
>> > There is no problem with code,We are closing the connections properely.
>> > This issue is occured in production side.We are highly suspecting that
>> > there is an issue with the Tomcat server( V7.0.52). First of all,Please
>> let
>> > us know if there is any bug regarding the Connection pool in tomcat
>> V7.0.52
>> > .If yes,tell me which version to be use to eradicate this issue.
>> > Again we are confirming that ,there is no problem with the code.
>>
>> This way we're back on my initial comment: "any bug regarding connection
>> pool" is quite a broad question to ask.
>>
>> * How many /concurrent/ connections does your production server handle?
>> * How many http handler (threads) did you configure on the machine that
>> has the 4000 database connections?
>> * How long are these connections leased from the pool on average / max?
>> * Have you tried reproducing this in a minimal code environment?
>>
>> Olaf
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> For additional commands, e-mail: users-help@tomcat.apache.org
>>
>>
>
>
> --
> S Saikumar
>



-- 
S Saikumar

Re: Connection pool issue was in with 7.0.52 version? And it is fixed in 7.0.78 version?

Posted by Sai Kumar <sa...@gmail.com>.
Hi ,
Need one help.I just seen this.
*Bug 53367* <https://bz.apache.org/bugzilla/show_bug.cgi?id=53367> - Database
failure may cause pool to hang - in bugzilla.,
My problem is something related to this case.And the fix included two
files..
1.FairBlockingQueue.java
2.Bug53367.java
Can you please tell me .how to replace or deploy those files and test my
case.
I have no idea about it.So please tell me clearly.

Thank you

On Fri, Jun 16, 2017 at 5:39 PM, Olaf Kock <to...@olafkock.de> wrote:

>
> Am 16.06.2017 um 14:00 schrieb Sai Kumar:
> > There is no problem with code,We are closing the connections properely.
> > This issue is occured in production side.We are highly suspecting that
> > there is an issue with the Tomcat server( V7.0.52). First of all,Please
> let
> > us know if there is any bug regarding the Connection pool in tomcat
> V7.0.52
> > .If yes,tell me which version to be use to eradicate this issue.
> > Again we are confirming that ,there is no problem with the code.
>
> This way we're back on my initial comment: "any bug regarding connection
> pool" is quite a broad question to ask.
>
> * How many /concurrent/ connections does your production server handle?
> * How many http handler (threads) did you configure on the machine that
> has the 4000 database connections?
> * How long are these connections leased from the pool on average / max?
> * Have you tried reproducing this in a minimal code environment?
>
> Olaf
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>


-- 
S Saikumar

Re: Connection pool issue was in with 7.0.52 version? And it is fixed in 7.0.78 version?

Posted by Olaf Kock <to...@olafkock.de>.
Am 16.06.2017 um 14:00 schrieb Sai Kumar:
> There is no problem with code,We are closing the connections properely.
> This issue is occured in production side.We are highly suspecting that
> there is an issue with the Tomcat server( V7.0.52). First of all,Please let
> us know if there is any bug regarding the Connection pool in tomcat V7.0.52
> .If yes,tell me which version to be use to eradicate this issue.
> Again we are confirming that ,there is no problem with the code.

This way we're back on my initial comment: "any bug regarding connection
pool" is quite a broad question to ask.

* How many /concurrent/ connections does your production server handle?
* How many http handler (threads) did you configure on the machine that
has the 4000 database connections?
* How long are these connections leased from the pool on average / max?
* Have you tried reproducing this in a minimal code environment?

Olaf


---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org


Re: Connection pool issue was in with 7.0.52 version? And it is fixed in 7.0.78 version?

Posted by Sai Kumar <sa...@gmail.com>.
There is no problem with code,We are closing the connections properely.
This issue is occured in production side.We are highly suspecting that
there is an issue with the Tomcat server( V7.0.52). First of all,Please let
us know if there is any bug regarding the Connection pool in tomcat V7.0.52
.If yes,tell me which version to be use to eradicate this issue.
Again we are confirming that ,there is no problem with the code.


On Fri, Jun 16, 2017 at 5:16 PM, Olaf Kock <to...@olafkock.de> wrote:

> If you don't have 4000 concurrent connections coming in to your
> application server, this sounds suspiciously like your code gets a
> connection from the pool and never returns it. Naturally, once the
> connection has been used, it will turn idle (as no more statements are
> executed), but if the connection pool does not know that nobody is
> working on it any more, it won't hand the existing connection out to
> anybody else.
>
> Inspect your code if you ever call connection.close(), which should
> return the connection to the pool.
>
> Olaf
>
>
> Am 16.06.2017 um 12:40 schrieb Sai Kumar:
> > We are using 4000 connections for the particular DB in connection
> > pool.Somehow,those 4000 connections are utilised in our production
> > environment.If any new request is coming ,it is unable to fetch a
> > connection because all the connections are utilised.But ,The actual
> problem
> > is after processing the request the connection pool will leave the
> existing
> > connection and ready for a new request to process.This is not happening
> > here.All 4000 connections are never released.
> >
> > After processing ,all Active connections are moved to idle state ,but the
> > idle connections are not re connecting to any other request later.
> >
> > Please help us on this ASAP.
> >
> > On Fri, Jun 16, 2017 at 3:49 PM, Olaf Kock <to...@olafkock.de> wrote:
> >
> >> Sai Kumar,
> >>
> >>
> >> Am 16.06.2017 um 12:06 schrieb Sai Kumar:
> >>> Hi ,
> >>>
> >>> We are using following tomcat version
> >>>          Apache Tomcat/7.0.52
> >>>          Server number:  7.0.52.0
> >>> and currently we are facing a problem with this one.
> >> While you give some description of things that happen in your
> >> environment, it would help to reproduce them in a minimal system, e.g.
> >> to provide a test case that demonstrates the issue in the simplest
> >> possible way.
> >> So far, your description gives little clue if your own webapp is
> >> exhausting the connections itself, e.g. forgetting to return connections
> >> to the pool. Ideally this would be a little code that exposes the
> >> problem, together with steps to reproduce.
> >>
> >>> 1.Is there any Connection pool issue in the 7.0.52 version?
> >>> 2.And it is fixed in 7.0.78 version? Or else tell me in which version
> MY
> >>> CASE issue is fixed.
> >> I doubt that anyone would take on the "any" in question 1 - unless
> >> somebody is actively aware of an actual bug in that version.
> >> Question 2 would easily be answered with the minimal reproduction case
> >> that I've talked about above.
> >>
> >> Olaf
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >> For additional commands, e-mail: users-help@tomcat.apache.org
> >>
> >>
> >
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>


-- 
S Saikumar

Re: Connection pool issue was in with 7.0.52 version? And it is fixed in 7.0.78 version?

Posted by Olaf Kock <to...@olafkock.de>.
If you don't have 4000 concurrent connections coming in to your
application server, this sounds suspiciously like your code gets a
connection from the pool and never returns it. Naturally, once the
connection has been used, it will turn idle (as no more statements are
executed), but if the connection pool does not know that nobody is
working on it any more, it won't hand the existing connection out to
anybody else.

Inspect your code if you ever call connection.close(), which should
return the connection to the pool.

Olaf


Am 16.06.2017 um 12:40 schrieb Sai Kumar:
> We are using 4000 connections for the particular DB in connection
> pool.Somehow,those 4000 connections are utilised in our production
> environment.If any new request is coming ,it is unable to fetch a
> connection because all the connections are utilised.But ,The actual problem
> is after processing the request the connection pool will leave the existing
> connection and ready for a new request to process.This is not happening
> here.All 4000 connections are never released.
>
> After processing ,all Active connections are moved to idle state ,but the
> idle connections are not re connecting to any other request later.
>
> Please help us on this ASAP.
>
> On Fri, Jun 16, 2017 at 3:49 PM, Olaf Kock <to...@olafkock.de> wrote:
>
>> Sai Kumar,
>>
>>
>> Am 16.06.2017 um 12:06 schrieb Sai Kumar:
>>> Hi ,
>>>
>>> We are using following tomcat version
>>>          Apache Tomcat/7.0.52
>>>          Server number:  7.0.52.0
>>> and currently we are facing a problem with this one.
>> While you give some description of things that happen in your
>> environment, it would help to reproduce them in a minimal system, e.g.
>> to provide a test case that demonstrates the issue in the simplest
>> possible way.
>> So far, your description gives little clue if your own webapp is
>> exhausting the connections itself, e.g. forgetting to return connections
>> to the pool. Ideally this would be a little code that exposes the
>> problem, together with steps to reproduce.
>>
>>> 1.Is there any Connection pool issue in the 7.0.52 version?
>>> 2.And it is fixed in 7.0.78 version? Or else tell me in which version MY
>>> CASE issue is fixed.
>> I doubt that anyone would take on the "any" in question 1 - unless
>> somebody is actively aware of an actual bug in that version.
>> Question 2 would easily be answered with the minimal reproduction case
>> that I've talked about above.
>>
>> Olaf
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> For additional commands, e-mail: users-help@tomcat.apache.org
>>
>>
>


---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org


Re: Connection pool issue was in with 7.0.52 version? And it is fixed in 7.0.78 version?

Posted by Sai Kumar <sa...@gmail.com>.
We are using 4000 connections for the particular DB in connection
pool.Somehow,those 4000 connections are utilised in our production
environment.If any new request is coming ,it is unable to fetch a
connection because all the connections are utilised.But ,The actual problem
is after processing the request the connection pool will leave the existing
connection and ready for a new request to process.This is not happening
here.All 4000 connections are never released.

After processing ,all Active connections are moved to idle state ,but the
idle connections are not re connecting to any other request later.

Please help us on this ASAP.

On Fri, Jun 16, 2017 at 3:49 PM, Olaf Kock <to...@olafkock.de> wrote:

> Sai Kumar,
>
>
> Am 16.06.2017 um 12:06 schrieb Sai Kumar:
> > Hi ,
> >
> > We are using following tomcat version
> >          Apache Tomcat/7.0.52
> >          Server number:  7.0.52.0
> > and currently we are facing a problem with this one.
> While you give some description of things that happen in your
> environment, it would help to reproduce them in a minimal system, e.g.
> to provide a test case that demonstrates the issue in the simplest
> possible way.
> So far, your description gives little clue if your own webapp is
> exhausting the connections itself, e.g. forgetting to return connections
> to the pool. Ideally this would be a little code that exposes the
> problem, together with steps to reproduce.
>
> > 1.Is there any Connection pool issue in the 7.0.52 version?
> > 2.And it is fixed in 7.0.78 version? Or else tell me in which version MY
> > CASE issue is fixed.
> I doubt that anyone would take on the "any" in question 1 - unless
> somebody is actively aware of an actual bug in that version.
> Question 2 would easily be answered with the minimal reproduction case
> that I've talked about above.
>
> Olaf
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>


-- 
S Saikumar

Re: Connection pool issue was in with 7.0.52 version? And it is fixed in 7.0.78 version?

Posted by Olaf Kock <to...@olafkock.de>.
Sai Kumar,


Am 16.06.2017 um 12:06 schrieb Sai Kumar:
> Hi ,
>
> We are using following tomcat version
>          Apache Tomcat/7.0.52
>          Server number:  7.0.52.0
> and currently we are facing a problem with this one.
While you give some description of things that happen in your
environment, it would help to reproduce them in a minimal system, e.g.
to provide a test case that demonstrates the issue in the simplest
possible way.
So far, your description gives little clue if your own webapp is
exhausting the connections itself, e.g. forgetting to return connections
to the pool. Ideally this would be a little code that exposes the
problem, together with steps to reproduce.

> 1.Is there any Connection pool issue in the 7.0.52 version?
> 2.And it is fixed in 7.0.78 version? Or else tell me in which version MY
> CASE issue is fixed.
I doubt that anyone would take on the "any" in question 1 - unless
somebody is actively aware of an actual bug in that version.
Question 2 would easily be answered with the minimal reproduction case
that I've talked about above.

Olaf

---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org