Not a concern - and here is why:-
More specifically: R=read replica count W=write replica count N=replication factor Q=QUORUM (Q = N / 2 + 1)
If W + R > N, you will have consistency
The problem is where to store the session data. If the session need to be accessible by more than one web servers, the external storage is needed.
Cassandra only supports eventual consistency. If web server w1 saves the session at node 1 of cassendra while web server w2 retrieve the session from different node, if these two requests are close enough, there is a chance what w2 retrieved is different from what w1 saved. Is it a concern?
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From: buddhasystem [mailto:email@example.com]
Sent: Tuesday, February 01, 2011 9:42 AM
Subject: Re: cassandra as session store
Most if not all modern web application frameworks support sessions. This
applies to Django (with which I have most experience and also run it with
X.509 security layer) but also to Ruby on Rails and Pylons.
So, why would you re-invent the wheel? Too messy. It's all out there for you
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