[TYPO3-english] Analysing performance problems

[Mark Roemermann]

Hi Graham,

I also had periodic lockups in the backend in the past on some shared
virtuozzo hosts with ImageMagick.  I think it is when thumbnails are
generated in the backend, and scaled images for the front end.  If you
can get console access you will see a whole bunch of convert commands
maxing out the CPUs.

I found the non-responsiveness in the backend would last for around
20sec or so until the images where regenerated and then everything would
come good again, which seems similar to your symptoms.

Perhaps you could try disabling image processing [GFX][image_processing]
= 0 from the install tool temporarily, clearing the cache etc and trying
again to see if you still get the problem? (obviously if its in
production that could cause a few problems with images).

Moving to vmware VPS' with a bit more CPU grunt and properly configuring
opcode caching removed the impression of slow responsiveness for me even
with lots of image processing.

Cheers.

On 10/09/2013 12:41 AM, Graham Knight wrote:
> Hi,
> 
> I am experiencing occasional periods of very poor performance on a TYPO3
> (4.5.22) site. When this occurs pages may take up to a minute to be
> delivered. Both normal pages and the TYPO3 backend seem equally
> affected. This does not seem to be a network problem - the time seems to
> be lost at the server. I do not have command line access so the main
> diagnostic tools I have are those provided by TYPO3 itself. I have read
> several articles on TYPO3 performance tuning but these invariably refer
> to tools I am not able to use. The hosting company is not very helpful ...
> 
> I would be very grateful for any suggestions of where to look for
> problems and, perhaps, how best to use TYPO3 logging tools to locate the
> problem. I have been using the Admin Panel to try see where the delays
> occur. Is there documentation somewhere on this? For example, in the
> Typoscript section, what is the meaning of the columns "Time" "Own" and
> "Sub"?
> 
> Graham Knight
> 
> 
>