[Zope-DB] Re: Zope-DCOracle2 vs Tomcat-JDBC performance

[Umberto Nicoletti]

OK, we'll try that that asap.

Still this does not explain the perfomance gain when using query caching.
We ran the same test with query caching (settings: max 2000, cache 100, 
time 60) turned on and got MUCH better results ( only 7 times slower 
than Tomcat and average response time under 1 sec).
I would believe that those security check would be done also with cached 
results...

Regards,
umberto

Matthew T. Kromer wrote:
> Umberto Nicoletti wrote:
> 
>> Hi all,
>> we're proud users of Zope, but recently we ran into some performance
>> issues.
>>
>> We have some Zope applications that are database (Oracle) intensive and
>> recently experienced some *huge* slowdowns when under heavy usage. We
>> had no problems before because the usage was modest (under 5 concurrent
>> users).
>> Since this is SHOW STOPPER for us we decided to spend some time and 
>> investigate further. We took a server and installed Zope 2.6.1, python 
>> 2.1.3 and DCOracle2 1.3b on Suse
>> Linux 8.0. On the same server we installed jakarta tomcat 4.1.24 with 
>> Sun JDK 1.4.1_02 and Oracle JDBC.
>>
>> On another server (identical HW and SW) we have an Oracle 8.1.7 
>> instance and so we ran some simple queries against it from Zope and 
>> Tomcat.
>>
>> Result is that with small pages in both size and number of records 
>> (under 5) displayed Zope is head to head with Tomcat.
>>
>> With larger pages (about 50 records displayed with no whatsoever html
>> tables or other embellishment) Tomcat is MUCH faster (see below).
> 
> 
> 
> As Dieter pointed out, this is probably the security mechanim doing a 
> linearly increasing cost to check each result you want to display in 
> your ZPT.
> 
> The "easiest" thing to do to effect a speedup is to put the 
> per-result-row renderer into an external method -- call it with your 
> query results, and let it format the HTML to be placed back into your 
> ZPT page.  This isn't necessarily elegant, but ought to do the job for you.
> 
> Alternatively, if you have tight control over your environment, you CAN 
> look at replacing the Zope Security Manager with one with checks more 
> optimized for your environment.  This isn't a trivial task, but it can 
> be done.
>