Re: Lockup fetching from database

Hi Brendan,

I'd be looking at the underlying cause before timing out. This is a pretty robust system usually.

There is a query timeout in the backend if that is causing the problem.

Is this a very long query ?

Dave

On 13-Jan-06, at 10:56 AM, Brendan Duddridge wrote:

Hi,

I'm running PostgreSQL 8.1 on OS X Server 10.4.3 using postgresql-8.1-404.jdbc3.jar and I'm experiencing some lockups when querying from the database through our java WebObjects program.

Here is a dump of the thread where the problem occurs:

"CSThreadPoolThread-0" prio=5 tid=0x00563ab0 nid=0x1894600 runnable [f1111000..f1112ac0]

       at java.net.SocketInputStream.socketRead0(Native Method)

        at java.net.SocketInputStream.read(SocketInputStream.java:129)

        at java.io.BufferedInputStream.fill(BufferedInputStream.java:183)

        at java.io.BufferedInputStream.read(BufferedInputStream.java:201)

        - locked <0x541cb7f8> (a java.io.BufferedInputStream)

        at org.postgresql.core.PGStream.ReceiveChar(PGStream.java:254)

        at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1163)

        at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:188)

        - locked <0x541c8860> (a org.postgresql.core.v3.QueryExecutorImpl)

        at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:430)

        at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:332)

        at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:324)

        at com.webobjects.jdbcadaptor.JDBCChannel._bindInputVariablesWithBindingsAndExecute(JDBCChannel.java:237)

        at com.webobjects.jdbcadaptor.JDBCChannel._evaluateExpression(JDBCChannel.java:303)

        at com.webobjects.jdbcadaptor.JDBCChannel.evaluateExpression(JDBCChannel.java:261)

        at com.webobjects.eoaccess.EOUtilities._rawRowsForSQL(EOUtilities.java:584)

        at com.webobjects.eoaccess.EOUtilities.rawRowsForSQL(EOUtilities.java:550)

        at ca.shopshop.ssmodel.Merchant.deactivateProductsForMerchantHavingNoOtherMerchantOffers(Merchant.java:614)

        at ca.shopshop.ssmodel.Merchant.deactivateMerchant(Merchant.java:685)

        at MerchantAccountStatusCheckerThread.performAction(MerchantAccountStatusCheckerThread.java:131)

        at com.clickspace.csutilities.threads.DatabaseUpdateThread.run(DatabaseUpdateThread.java:41)

        at com.clickspace.csutilities.threads.CSThreadPool$ThreadPoolThread.run(CSThreadPool.java:200)

So it seems that it's locking up retrieving data from the database. Is there a timeout parameter or something that can be set so if it takes too long to retrieve from the database I can handle an exception and continue on with my program? Right now all the other threads in my application start to block waiting for this one to complete and eventually my entire application instance locks up.

Thanks,

____________________________________________________________________
Brendan Duddridge | CTO | 403-277-5591 x24 |  brendan@clickspace.com

ClickSpace Interactive Inc.
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