[Zope-DB] Re: Zope-DCOracle2 vs Tomcat-JDBC performance
Matthew T. Kromer
Tue, 27 May 2003 11:49:19 -0400
Umberto Nicoletti wrote:
>> Well, there are ways to trace DCOracle2's timing -- so you can look
>> for places where DCOracle2 is causing slowdowns.
> That's cool. Should I use the profiler to do this?
Well, the way you enable DCOracle2 tracing is by setting the environment
variables DCO2TRACEFLAGS and DCO2TRACELOG -- Trace codes 33 and 34
track oracle calls and returns, so you can
and restart Zope -- and it will log *large* amounts of data to
dco2.trc. The first column in the log is a timestamp, so between any 33
and 34 codes for the same call you can see how long Oracle took to
execute that particular call. The trace flags is a binary OR of trace
codes, based on the README -- so 47 = 1 + 2 + 4 + 8 + 32. This is
Oracle calls, Oracle returns, Oracle errors, and thread context switches.
However, I dont actually expect the DCOracle2 database adapter layer to
be the issue -- at least, not directly. I do not know how well it will
perform for you though with large numbers of connections to the database.
If you do try turning on this tracing and just inspecting the trace
file, you may be able to spot some significiant time jumps interspersed
with thread switches -- if you see those, that can be significant.
>> Note that Zope's security policy is still going to check access to
>> every element returned by a database adapter, whether or not it is
> That's what I supposed and Dieter confirmed.
> Thanks to all of you helping me out...
You *may* be able to install the zope call profiler and get some numbers
for an individual request to see where it is spending its time. I'd give
that a go to see what you can see.
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