[Zope-DB] ZSQL parallelism problem

M.-A. Lemburg mal@lemburg.com
Sat Aug 2 15:33:11 EDT 2003

Kent Hoxsey wrote:
>>M.-A. Lemburg wrote:
>>It's possible that your queries are locking the database or
>>part of it, or that the two queries introduce a dead-lock
>>situation. That shouldn't stop Zope from serving non-database
>>related requests, though.
> A few more details: the queries are against an Oracle 8 (not 8i)
> database, make no data modifications, and complete in the 
> expected amount of time.
> I'm not seeing any unusual activity, except for the fact that the
> main Zope process seems to block. I have a ton of memory on the
> machine, and the cpu is basically idle waiting for the db to
> return, so I'd be very happy to consume resources and still have
> requests satisfied.
> I thought that increasing the number of threads would fix things,
> but it hasn't changed anything. Could this be a Windows issue?
> It's looking like I'm going to have to spend some time in the
> debugger to figure this thing out.

With mxODBC Zope DA, the main process should not block since
mxODBC releases the Python global interpreter lock during IO
operations to the database so other threads can continue
to run.

Marc-Andre Lemburg

Professional Python Software directly from the Source  (#1, Aug 02 2003)
 >>> Python/Zope Products & Consulting ...         http://www.egenix.com/
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