[Zope3-Users] Re: Performance

[Tom Dossis]

David Johnson wrote:
> Okay. I think I figured it out. It seems that images and large objects are
> the main culprit.  We have very few images, mainly just icons for the
> content types and tabs.  
> 
> I discovered this by using lynx and with IE disabling images.  
> 
> So the new question is: how do I speed up image downloading? I'm guessing
> this has something to do with the ZODB?

Hi David,

Here's some 'benchmarks' for you to compare against.

I accessed images both as resources and content objects.  Though there
was some difference b/w them it wasn't by any order of magnitude....

I used a recent Zope3 version from svn.zope.org.  From the results it
looks like data bandwidth may be a factor to consider.

Also my benchmark client is written in python using twisted and it also
adds it's own (significant) overhead.

I also ran some tests against Zope instances and ZEO (results not
included), which didn't turn up any weird result.


object=neptune.jpg size=3.39MB


1/ Accessed as resource, content is served from the file system..

Requests:    20
Errors:      0
Async level: 8
kBytes rcvd: 71097.0
Total time:  4.08 sec

Req rate:    4.9 req/sec
Data rate:   17416.7 kB/sec
Get ave:     0.204 sec

 #Req  #Err Get(ave) (min)  (max)    kB/s  URL
   20     0   1.458  0.855  1.695  2438.4
http://localhost:8082/@@/neptune.jpg


2/ Accessed as a Image content (ZODB) object with a Zope/ZODB instance..

Requests:    20
Errors:      0
Async level: 8
kBytes rcvd: 71097.0
Total time:  4.09 sec

Req rate:    4.9 req/sec
Data rate:   17397.5 kB/sec
Get ave:     0.204 sec

 #Req  #Err Get(ave) (min)  (max)    kB/s  URL
   20     0   1.462  0.867  1.685  2431.2
http://localhost:8082/content/neptune.jpg



object=sts.jpg size=371kB


3/ Smaller image accessed as resource object

Requests:    100
Errors:      0
Async level: 8
kBytes rcvd: 37996.2
Total time:  1.08 sec

Req rate:    92.8 req/sec
Data rate:   35274.5 kB/sec
Get ave:     0.011 sec


 #Req  #Err Get(ave) (min)  (max)    kB/s  URL
  100     0   0.085  0.035  0.109  4456.0  http://localhost:8082/@@/sts.jpg


4/ Smaller image accessed as content object

Requests:    100
Errors:      0
Async level: 8
kBytes rcvd: 37996.2
Total time:  1.41 sec

Req rate:    70.7 req/sec
Data rate:   26870.1 kB/sec
Get ave:     0.014 sec

 #Req  #Err Get(ave) (min)  (max)    kB/s  URL
  100     0   0.112  0.042  0.156  3381.7
http://localhost:8082/content/sts.jpg