Mattermost-server: loadtest: add file descriptors limit sanity check to the agent

[streamer45]

Introduction

This is a load-test specific issue to be implemented and submitted under the official load-test tool repository.

Our load-test tool is used to test Mattermost application under heavy load, simulating real-world usage of a server installation at scale.

Description

Load-test agents require 1 file descriptor per simulated user (ws connection) plus a fixed amount (up to 500) for the HTTP connections pool.

When running either ltapi or ltagent commands we should do a sanity check to make sure the current file descriptors limit (syscall.RLIMIT_NOFILE) is compatible with the configured maximum number of users and return an error otherwise.

Need help?

If you have questions about the ticket or you need any help, feel free to post your question in ~Developers: Performance or contact claudio.costa in https://community.mattermost.com/

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JIRA: https://mattermost.atlassian.net/browse/MM-30334

[agnivade]

@CandyZack - Would you be interested in taking this one?

[CandyZack]

@agnivade Sure. I will give it a try! Assign me this issue.

[agnivade]

Hi @CandyZack - how is it going with this? Let us know if we can help in any way.

[CandyZack]

@agnivade Sorry for delay. Was loaded with work 😩, and I missed this.
I need help with testcases. I have mentioned this in the PR