
Some fun with Redis Cluster testing - janerik
http://antirez.com/news/69
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film42
I think this is a great lesson on testing. I'm excited to see what else he
finds.

~~~
pquerna
Why is this a great lesson?

The test is not repeatable. There was a power outage. Random machine
configurations on random network conditions. These are all great ways to
stress redis-cluster, which is still young, but they are not repeatable tests.

They are not great tests. Great tests would be a script that can run every 24
hours over a group of servers, simulating or creating similar events and
network conditions. Then when a code change is made, you can actually observe
if it made things better.

Driving a car across the Sahara Desert can be a good event, but it shouldn't
replace Crash Tests in a Lab environment.

~~~
antirez
Hi pquerna, what you describe is exactly what the Redis Cluster standard test
will be (the one that will implement unit tests, not just fuzzy testing like
the one I did now). Probably to make it easy to run in different platforms,
what is needed is direct partitions simulation support into Redis Cluster,
what I mean is, an explicit API to filter at higher level specific nodes and
clients.

However I believe that I'll still do the kind of tests described in the blog
post since the fact itself that these tests are so "home brew" and cheap make
the conditions extremely random and are good at spotting actual real-world
deficiencies.

