Hi Matt,

Thanks for your response.


Ø  I found that this reduced token validation performance by approximately 2x.
Compared to what? Having no revocation events at all?


Ø  I did not go into more detail on where the slowness was coming from.
As you know, when list-revoked-tokens is called, we do a 
cleanup-expired-revocation-events operation. But, most of the time there is 
nothing to delete (since list-revoked-tokens is called so frequently). So, a 2x 
performance degradation is surprising. I would love to see a detailed analysis 
of where exactly it is happening. This will also be required so that we can 
come up with a right fix for this problem.

Thanks,
Deepti

From: [email protected] [mailto:[email protected]] On Behalf Of Matt Fischer
Sent: Tuesday, June 23, 2015 2:58 PM
To: Ramakrishna, Deepti
Cc: [email protected]; Bhandaru, Malini K
Subject: Re: [Openstack-operators] Load on Keystone database

Deepti, sorry for replying off-list before, that was an accident. I have some 
new info though:

I ran some numbers on this today just from a general benchmark POV. We had 900 
revocation events in our system as the result of some automated testing. I 
found that this reduced token validation performance by approximately 2x. I did 
not go into more detail on where the slowness was coming from. This setup is 
also using fernet tokens, so only revocations are in the db. We are now 
re-examining some of our test automation to keep the number of revocation 
events low.  We don't typically have more than a few revocation events at a 
time unless we're running some tests.

In addition to tests, I believe the revocations are created when you log-out of 
Horizon. I'm not sure whether that's a change we made or whether it's in the 
main Horizon.

I think that this area may bear some more investigation by the keystone team.

On Wed, Jun 3, 2015 at 12:07 PM, Ramakrishna, Deepti 
<[email protected]<mailto:[email protected]>> wrote:
Hi,

I am currently working on fixing bug 
#1456797<https://bugs.launchpad.net/keystone/+bug/1456797>, which is about 
building a mechanism to purge expired token revocation events from keystone 
database. While investigating this bug, I noticed that we actually already 
purge expired revocation events, but we do it from the list-revocation-events 
API. Since the list-revocation-events API is so frequently called, this 
translates to high frequency of delete calls on the keystone database. I was 
wondering if any of you have noticed issues arising due to this load on 
keystone db. If so, I would be interested in hearing about your experience. If 
the current design unduly stresses the db, I can move out the purge feature 
from the list-revocation-events API.

Thanks,
Deepti


_______________________________________________
OpenStack-operators mailing list
[email protected]<mailto:[email protected]>
http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators

_______________________________________________
OpenStack-operators mailing list
[email protected]
http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators

Reply via email to