Excessive memory usage for PHP-FPM

[enricostahn]

What is the memory overhead added by Dynatrace? Just looking at Nginx and now PHP-FPM it seems fairly excessive.

I have just enabled for PHP-FPM and memory consumption went from 160ish to 400ish.

[skrystosik]

It should not be like that. I suggest opening support ticket for this case.

Sebastian

[Julius_Loman · Accepted solution]

Around 200MB increase should be OK according to the docs. Do you have any request attributes defined or SQL bind variables capture turned on? Have you increased the limit of new purepaths to be caputred from the default (1000/minute)? (Dynatrace Managed only) There are several cases when the footprint becomes slightly larger.

[enricostahn]

@Julius L. I have not adjusted any thresholds. It’s a fairly new installation with none of the adjustments you mentioned.

We had the same issues with Nginx. The root-cause was that Nginx has too many workers. After reducing the workers to 1 the memory overhead became a lot less.

Unfortunately we don’t have the same luxury with PHP-FPM.

I will keep monitoring it over the next week and report back.