MemcachedStorage and IdP3

[Manuel Haim]

On 23.08.2017 20:49 O'Dowd, Josh wrote:
> But what you said makes me think that keys are not replicated across nodes.

It's just as Marvin said: The underlying spymemcached library does not
replicate information across nodes. Technically speaking, it's just a
cache which may get lost. However, you could try and use a "repcached"
server instead of a "memcached" server: http://repcached.lab.klab.org/

You could also try other infrastructures like Hazelcast which come with
a memcached interface and data replication mechanisms.

On my IdPv2 implementation of the Memcached StorageService, each IdP
node also had to keep a local copy of the Java objects used (there was
no trigger for object changes, thus I had to merge the current session
object with memcached at the start and end of a request). Combined with
session stickyness on your loadbalancer, it required to take down BOTH
an IdP node AND a memcached node in order to lose a cached object.

Kind regards,
Manuel