Slow DJango 1.4 with timeouts on Helicon Zoo

[SyRenity Profile]

We finally done migrating to Helicon Zoo on Windows 2012 (from ISAPI 2008).
The problem is that users complain about random slowdowns and timeouts with the application.

From reading through the net, it seem to be a known problem with Python 32 bit running on top of Windows 2012 64-bit.
Any plans to switch to the 64-bit version? Otherwise, any idea what else I can check?

(Just to note, the problem is not entirely Zoo related, as runserver also gives same slow results).

Thanks in advance!

[Ruslan]

Hello,

you can try to install and use Python x64 by himself:

1. Install Python x64
2. Create custom Zoo engine for wsgi apps on Python x64
3. Update engine in app web.config and recreate app virtualenv with Python x64 executable.

Example of custom Zoo engine:

Code: Select all

<heliconZooServer>
  ...
  <userEngines>
    <clear />
    <add name="python.x64.2.7.wsgi" displayName="Python x64 2.7 wsgi"
            fullPath="%SystemDrive%\python27x64\python.exe" arguments="%SystemDrive%\Zoo\Workers\python\zoofcgi.py"
            transport="NamedPipe" protocol="fastcgi" portLower="49152" portUpper="65535"
            maxInstances="0" minInstances="1" timeLimit="0" gracefulShutdownTimeout="30" memoryLimit="0">
      <environmentVariables>
        <clear />
      </environmentVariables>
    </add>
  </userEngines>
</heliconZooServer>


Thanks!

[Ruslan]

Could you please also clarify how the slowdown occurs. Does it happen for the first request only? Or does it happen sporadically? Or is it simply low RPS? Are all processor cores heavily loaded?

[SyRenity Profile]

Forgot to mention - the CPU is the leading cause for that.

As we running the systems on Amazon AWS, we see their memory-oriented instances practically over-consumed by the CPU.
Switching to CPU-oriented instances helps a bit, but we still see the cores being filled up to 80%-90% by python.exe process usage on every request.

[SyRenity Profile]

Could you please also clarify how the slowdown occurs. Does it happen for the first request only? Or does it happen sporadically? Or is it simply low RPS? Are all processor cores heavily loaded?

* The slow-downs are caused by high CPU usage, consuming up to 80%-90% of the available CPU time
* It happens on every request, every-time
* All available processor cores become overloaded

[SyRenity Profile]

Switching to 64-bit solved the issue! Apparently the double-virtualization (64-bit WOW -> AWS Xen) has caused the issues.

Any idea how it's possible to install just the Zoo modules, without the Python as well?
Also, a VERY good idea will be to ship 64-bit Python version with Zoo, this problem might happen on any AWS EC machine.

[Ruslan]

Thank you for reporting! We plan to add Python x64 in Zoo feed later.

> Any idea how it's possible to install just the Zoo modules, without the Python as well?

Just install 'Zoo Module' product in Web Platform Installer, not Python Hosting Package.

[SyRenity Profile]

Thanks.