@incubator.apache.org
Subject: Re: pessimistic locking
Patrick,
Just to clarify... If we set up OpenJPA in this manner
(Optimistic to false
and the Read and Write Lock levels to None), then all
transactions would
then be running in Pessimistic mode, right? That is, we
don't have the
means of being
We'd also have to set the LockManager property to pessimistic to get
database locks. And just to build on what Patrick is saying: OpenJPA
can do locking within optimistic transactions on individual
instances, but you have to set a lock level on the FetchPlan in code,
which I don't think
, February 13, 2007 10:59 AM
To: open-jpa-dev@incubator.apache.org
Subject: Re: pessimistic locking
We'd also have to set the LockManager property to pessimistic to get
database locks. And just to build on what Patrick is saying:
OpenJPA
can do locking within optimistic transactions
This benchmark runs best with a combination of optimistic locking
(most cases) and pessimistic locking (some specific uses identified
explicitly in the code).
Where concurrency is low, an optimistic approach works well. In
specific cases, optimistic results in bad performance due
Comments from the experts here?
Craig
Begin forwarded message:
From: Scott Oaks [EMAIL PROTECTED]
Date: February 12, 2007 11:45:52 AM PST
To: [EMAIL PROTECTED]
Subject: pessimistic locking
Reply-To: [EMAIL PROTECTED]
The SPEC organization is in the process of developing a JPA-based
benchmark
I think you also want to set openjpa.Optimistic to false. That
will default to non-optimistic transactions.
Setting the other properties (openjpa.LockManager,
openjpa.ReadLockLevel, openjpa.WriteLockLevel) are probably
unnecessary.
On Jan 12, 2007, at 11:56 AM, Ritika Maheshwari
