Alert creation is very slow (20-25 seconds)

[trocade]

Work Environment

Question	Answer
OS version (server)	Ubuntu 18.04 LTS
OS version (client)	Ubuntu 16.04 LTS (Via python API)
TheHive version	4.0.2
Package Type	DEB
Browser type & version	N/A

Problem Description

We are in the progress of migrating from thehive3 to thehive4 and are currently working on the alerting part.
When creating a alert in thehive3.5 it takes a few seconds but in thehive4 the same operation takes 20-25seconds.

Steps to Reproduce

1. Send alert using API

Complementary information

Singe system setup using local filesystem as provider and one cassandra instance.
Aprox. 60.000 alerts (imported from thehive3)
nginx proxy for certificates

I can not find information on how to debug the API calls so the only log entries we have are these:

Application

2020-12-08 12:09:04,690 [INFO] from org.thp.scalligraph.AccessLogFilter in application-akka.actor.default-dispatcher-4915 [00000fd9|] 127.0.0.1 POST /api/alert took 23336ms and returned 201 1794 bytes

NGINX

"POST /api/alert HTTP/1.1" 201 1794 "-" "python-requests/2.22.0"

[rriclet]

This issue has been fixed with #1731, included in release 4.1.0.
Feel free to re-open this issue if you still notice slow performance.