On 29.5.2014 21:12, Bill Burke wrote:
I'd like to have a hangout next week on this. There's really
4 areas to
focus on:
1. Set up a good performance test and get a baseline on current code.
I've
already did some performance tests longer time ago when comparing
model implementations. Those are at "testsuite/performance" . These are
just Java tests, which are directly using model API (no end-to-end HTTP
tests ATM).
It's based on JMeter and it allows to configure number of concurrent
workers and number of "iterations" for each worker. For example test for
creating users with 10 workers and each worker creating 100 users means
1000 created users in total. Also in property files you can configure
number of users to create, realms where to create users etc.
Just figured out that tests doesn't work atm, but will try to possibly
fix and send PR also with some instructions.
2. Database caching. There are multiple approaches.
* Our caches will be read-mostly except for user session management.
I think that
in very big systems there might be also big number of user
registrations . And each user can change his account, so it might be big
number of edit actions, which can user done by himself (for example
linking/unlinking social account).
* Write our own REST cache. My idea was to implement a new model
provider that delegates to the real underlying model provider. It would
send RESTful invalidation messages secured by keycloak in a clustered
environment. Maybe use Infinispan or some other local-only cache as the
backbone. I'm really really wary of using Infinispan (or other cache's)
clustering options. I'm not sure how well these guys work in cloud
clustered environments. And I'm not sure how well they've thought of
security.
* Use Hibernate 2nd level cache. Really wary of this as I don't know
how well Infinispan et. al. work in a cloud environment. I'd really
like something HTTP based and authenticated by Keycloak. I'm not sure
we'll be able to get the level of control here either that we need.
* Another reason for a custom cache, is, IMO, almost everything can be
stored in memory. Even users.
Reusing infinispan at last as local-only cache would
be nice as it
solves many other things, like for example eviction/expiration . It has
also support for transactions (but if we want to use it, we may need to
add JTA support...)
Creating our own model provider will add good control, but might be time
consuming tasks . Tricky part is invalidation IMO. For example when you
delete application, you should drop also all application roles, role
memberships, scopes and scope memberships and userSession links to this
application. In the end, it might drop almost whole cache:-)
But probably we need to focus especially on events, which will happen
often (like creating new userSession or registering new user) and ensure
that there is no invalidation of more things then needed in these
cases. But for example registration of new user should invalidate all
user queries as well (I mean realm.getUsers() , realm.searchForUser and
realm.searchForUserByuAttribute).
3. Clustering.
* Keycloak is not completely stateless. Specifically access codes are
stored in memory. We should be able to move this state information into
a cookie.
* User Session management is a huge issue as it is the only thing that
is write-mostly.
There is also some state on SocialRequestManager .
4. HTTP Cache-Control
* All themed static content should support a way to set up cache-control
headers.
* Admin REST api could do cache-control too if we had a way to determine
a version number or timestamp on model data. Not that important though
as, IMO, admin rest api isn't going to have a lot of volume.
I would add "pagination" support. I think we need pagination at least
for users, probably also for userSessions on clients (I mean
clientModel.getUserSessions() ). Maybe also for AuditProvider query results.
Marek