Non-blocking JDBC with Oracle OCI

I have been monitoring performance for a batch type application in a production environment over the last couple of weeks and all indications are that the blocking JDBC actions are the cause of performance issues in the application. The data access layer is built on Hibernate. And while HIbernate is a fine ORM, and does a great job of creating lightweight, fast individual pieces of SQL, I fear it is the sum of these parts that is causing our problems. I consistently see the Hibernate BatcherImpl getResultSet as consuming the most exclusive time in processing. Of course this is related to the structure of the target database as a lot of this time is being spent in execution.
What appears to be happening is that the executing threads are blocking until they get a response from the database. We are currently using Thin connections, on 10.2.x drivers. On last reading our processor queue length was as high as 70!! This is a clear indication of a CPU bottleneck.
I was wondering if it is possible to configure non-blocking JDBC using the OCI type connections instead of Thin connections....
Any advice someone could give on this topic would be much appreciated.
Thanks much in advance,
Jay

Hi Thomas,
Thank you for the reply. I am aware that only one statement can be executed on a connection at any given time, and we have connection pooling configured, so that's not a problem.
More specifically what I am looking for here is that when a thread executes a sql statement using a connection, it seems to block on the processor, it does not switch out, thus not allowing other work to be done while the database satisfies the sql statement. I was wondering if OCI connections were used would the thread switch out until a response was recieved from the database.

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Hello,
We found a potential bug in the kodo.jdbc.sql.OracleDictionary class
shipped as source with Kodo:
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public void setString (PreparedStatement stmnt, int idx, String
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This block seems to be intended for select statements but is called on
inserts/updates also. The latter causes a known problem with the Oracle
oci driver when settings CHAR columns as FixedCHAR, which reports an
ORA-01401 error (inserted value too large for column) when definitely no
column is too long. This does not happen with the thin driver.
We reproduced this with 8.1.7 and 9.2.0 drivers.
For us we solved the problem by subclassing OracleDictionary and removing
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Rainer Meyer
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while I'm using the oracle oci type driver I got the error but it works fine with the thin driver.
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with
raghu

while I'm using the oracle oci type driver I got the
error but it works fine with the thin driver.What is the error ?
so where should I the information regard this.I'm
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Post your JDBC URL and the exception you are getting if you are still having problems.

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Why folks afraid to use jdbc with oracle

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%

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*****************************************************8
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va:365)
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Best Regards,
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(1) A (Database)
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----(1.2) Y (schema)
---------(1.2.1) Number of tables belongs to y schema
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For example, users jdoe and sroe each have a table named my_table; jdoe has the "SELECT ANY TABLE" privilege and sroe doesn't. jdoe can get results from these SQL statements:
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select count(*) from jdoe.my_table;
select count(*) from sroe.my_table;user sroe can only do these:
select count(*) from my_table;
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Memory leakage with oracle oci driver

I have developed a Solaris8 client/server application using the JAVA IDL CORBA implementation. The client sends requests to the server to update the database (database is Oracle 8.1.7 and I connect to it using oci oracle drivers). Requests are sent one at a time. No concurrent connections. I have a static connection that I establish with database once I start the server. If that connection is lost for any reason (timeout or database faliure) the application tries automatically to reconnect to database. I have noticed that if the new connection to database fails and an sql exception is thrown, memory used by the application process increases. This memory is not garbage collected so application hangs. I tried similar behaviour with the oracle thin driver and things went fine. There was no memory leakage.
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I have noticed
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This memory is not
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I tried
similar behaviour with the oracle thin driver and
things went fine. There was no memory leakage.
I would really appreciate, if you can help me in this
since I can't use the thin driver because of failover
limitations.
I don't understand that last sentence at all.What I mean here is that instead of using the oci8 driver to connect to database I used the thin driver and kept everything else the same. I simulated the faliure to reconnect to database and based on the pmap command observations there was no memory leakage.
I want to know what is needed to be done in order to get a normal behavior once using the oci8 drivers.

Non Blocking Call with OCCI

Hi Everyone
I have searched through the whole OCCI documentation and could not find a way to make an asynchronous call to the database. you see the issue we have is that we need to cancel a call to the database if it does not return within the timeout value set. However, OCI does have the cancelling mechanism, but we have doned some testing and the Binding and Defining parameters call take to much of memory and and CPU. Once in a while it runs out of memory.
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andyman35uk wrote:
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The invalid handle was most likely the error handle, not the service context nor server handles as kmohan indicated above. The error handle needs to be allocated first.
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Non-blocking JDBC with Oracle OCI

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