Keystone performance degradation in 9.2 MU

[Pavel]

Looks like we got Keystone's performance degradation in 9.2 MU.

Here are the results for 436th build where no performance degradation was detected:
https://mirantis.testrail.com/index.php?/runs/view/24538

and here are the results for 440th build where significant performance degradation was found:
https://mirantis.testrail.com/index.php?/runs/view/24544

As you can see, we got about 15% performance degradation for validation operation and for authentication operation we got performance degradation at about 18 times comparatively to performance baselines in 9.1 MU.

Both test runs were performed using the same hardware environment (ENV-17 Lab of Performance QA Team). Installation procedure and cluster parameters were the same.

Since all 438-440th build have the same repos, I believe the root cause appeared in the 437th or in the 438th build.

[Boris Bobrov (bbobrov)]

Performance degradation happened between in ISO 437. 436 is the last good one. The only change between these ISOs is in MySQL: http://mirror.fuel-infra.org/mos-repos/ubuntu/snapshots/9.0-2016-10-26-114322.diff.txt . That's why i am assigning to MOS Linux team.

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/28076
Submitter: Pkgs Jenkins <email address hidden>
Branch: 9.0

Commit: dedade0b871c1d611954aced5d26bcd0a4594b2e
Author: Ivan Suzdal <email address hidden>
Date: Tue Nov 1 14:29:35 2016

Revert "Add mysql-server-wsrep-core-5.6-dbg package"

due to performance degradation

This reverts commit 381c4d2a618e44da4b89b4caf9bb03d386063100.

Closes-Bug: #1637572

Change-Id: Ic863a7731dda2c80395685c48ac3e67d1a349b3a

[Pavel (p.petrov)]

Fix verified for 501-th build: https://mirantis.testrail.com/index.php?/runs/view/25700
There is no such the significant performance degradation as it was observed on 440-th build where it was initially found.
Thus, MySQL related issue is fixed.