Re: [Proxool-developer] Connection release latency when using proxool with PostgreSQL

[Jean-Henry B. <ber...@ne...>]

The traces are not showing anything unusual, but I noticed another thing:
- I start with minumumConnectionCount set to, say, 30. Proxool is correctly
building 30, but the first time I need a connection it builds another 
one, and
another one and so on, every time a need a connection from the pool.
So it looks like the reusability is not working.
Again, it was working all right with Informix, but not with PostgreSQL.

The trace shows something like this when I start:
==========================================================================
0 [main] INFO org.logicalcobwebs.proxool.ProxoolFacade  - Proxool 0.8.2 
(05-Nov-2003 10:48)
39 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: proxool.driver=org.postgresql.Driver
39 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: 
proxool.url=jdbc:postgresql://pogo:5434/gex_runtime:user=postgres;password=post.gres
41 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: proxool.minimum-connection-count=30
42 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: proxool.maximum-active-time=4000
42 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Delegating 
property to driver: user=postgres
43 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: proxool.maximum-connection-lifetime=60000000
43 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: proxool.house-keeping-sleep-time=600000
43 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Delegating 
property to driver: password=********
44 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: proxool.verbose=true
44 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: proxool.trace=true
45 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: proxool.house-keeping-test-sql=select count(*) from 
sid_content_four;
45 [main] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - Recognised 
proxool property: proxool.maximum-connection-count=1000
207 [main] DEBUG org.logicalcobwebs.proxool.ShutdownHook  - Registered 
shutdownHook
226 [main] DEBUG org.logicalcobwebs.proxool.HouseKeeperController  - 
Registering 'globexplorer_0' house keeper
244 [main] DEBUG org.logicalcobwebs.proxool.HouseKeeperController  - 
Starting a house keeper thread
247 [HouseKeeper] INFO org.logicalcobwebs.proxool.globexplorer_0  - 
Proxool statistics legend: "s - r  (a/t/o)" > s=served, r=refused (only 
shown if non-zero), a=active, t=total, o=offline (being tested)
256 [HouseKeeper] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - 
000000 (00/00/00) - House keeping triggerSweep done
671 [Prototyper] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - 
Remembering default value: isReadOnly() = false
987 [Prototyper] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - 
org.postgresql.Driver does not support getHoldability. Proxool doesn't mind.
988 [Prototyper] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - 
org.postgresql.Driver does not support setHoldability. Proxool doesn't mind.
993 [Prototyper] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - 
Remembering default value: getTransactionIsolation() = 2
995 [Prototyper] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - 
Remembering default value: getTypeMap() = null
996 [Prototyper] DEBUG org.logicalcobwebs.proxool.globexplorer_0  - 
Remembering default value: getCatalog() = gex_runtime
==========================================================================

What exactly "Holdability" means? I noticed I have it with Informix, but 
not here.
Also, how one can programatically set the connection to be readOnly? I 
always use it as readOnly in what I try to do here and I noticed
proxool is setting it to default = false.
All the other properties are set in my server with something like:

info.setProperty("proxool.maximum-connection-count", connCount);

Thanks and best regards,
Jean



Jean-Henry Berevoescu wrote:

>
>
> bi...@lo... wrote:
>
>>Hi Jean,
>>
>>On Wed, 2003-12-10 at 11:52, Jean-Henry Berevoescu wrote:
>>
>>  
>>
>>>There is a problem in this new setup: the unused connections are released
>>>at a slower pace
>>>    
>>>
>>
>>Can you clarify what you mean by "released"? The life cycle is that a
>>connection is built, [served, returned,]* destroyed. Which bit is taking
>>a long time?
>>  
>>
> It is al acting in a weird way. What I do is build-use-returnToPool 
> but what I see
> is a lot of connections being created and a lot of them lingering in 
> TIME_WAIT
> state. It is not very clear why.
>
>>>The real problem is that I am expecting to reuse connections a lot 
>>>    
>>>
>>
>>By "reuse" do you mean serve the same connection lots of times? Serving
>>(and returning) a connection should be very quick.
>>  
>>
> Yes - the pattern of use is as I said before: create-use-returnToPool
>
>>Have you tried switching trace on? That will give you the performance of
>>your database calls. Could it be that the database is performing slowly
>>and that is what is causing many connections to be built?
>>
> I switched the tracing on for a short test, but I will do it again and 
> will take a
> closer look.
>
> Thanks,
> Jean
>
>>Regards,
>>Bill Horsman
>>
>>
>>
>>-------------------------------------------------------
>>This SF.net email is sponsored by: SF.net Giveback Program.
>>Does SourceForge.net help you be more productive?  Does it
>>help you create better code?  SHARE THE LOVE, and help us help
>>YOU!  Click Here: http://sourceforge.net/donate/
>>_______________________________________________
>>Proxool-developer mailing list
>>Pro...@li...
>>https://lists.sourceforge.net/lists/listinfo/proxool-developer
>>  
>>