# Dynamic inventory can take a long time to fetch hosts in group (aws\_ec2)

**URL:** <https://forum.ansible.com/t/dynamic-inventory-can-take-a-long-time-to-fetch-hosts-in-group-aws-ec2/37295>\
**Category:** Ansible Project\
**Created:** [November 2, 2022, 7:30pm UTC](https://forum.ansible.com/t/dynamic-inventory-can-take-a-long-time-to-fetch-hosts-in-group-aws-ec2/37295 "2022-11-02T19:30:47Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Josh\_K](https://avatars.discourse-cdn.com/v4/letter/j/e9bcb4/32.png) [@Josh\_K](https://forum.ansible.com/u/Josh_K)\
**Post date:** [November 2, 2022, 7:30pm UTC](https://forum.ansible.com/t/dynamic-inventory-can-take-a-long-time-to-fetch-hosts-in-group-aws-ec2/37295/1 "2022-11-02T19:30:47Z")

</div>

I have a dynamic inventory created with the aws\_ec2 inventory plugin. I added a new group and now my inventory is taking a noticeably long time to load:

groups:  
…  
u: “tags.get(‘Name’) | regex\_search(‘u[\d]+’)”

I’ve written a short python program to test how long this is taking:

import os  
import time

runs = 50

start = time.time()  
for i in range(runs):  
os.system(“ansible --list u”)  
end = time.time()

print(f"Runtime: {end - start:.2f} for {runs} runs")  
print(f"Avergae runtime: {(end - start) / runs:.2f}")

Some results:

runs | avg time per run (s)  
1 | 2.5  
5 | 4.4  
10 | 2.3  
25 | 5.3  
50 | 2.7

From these results I am concluding that sometimes this can take very long… 5 or more seconds to wait for a command like ansible --list u is brutal.

1. Why is this taking so long???
2. Is there a better way to accomplish what I have here?