Today I realised that although we have per-table metrics, they are not
*really* available by default. I was suprised to find that we don't have
(as far as I can tell) a document explaining why it is so, or how to enable
them anyway. Moreover, the more I investigated this issue, the more I
realised how little I know on Scylla's metrics - how they are calculated,
how they are collected, their different types, and so on.
So I sat down to figure out everything I wanted to learn about Scylla metrics,
and then wrote it all down in a new document, docs/metrics.md.
There are some missing pieces in this document marked by TODO, and probably
additional missing pieces that I'm not aware of, but I think this is already
a good start and can be (and should be) improved-on later.
We really need to have more of these documents describing various Scylla
subsystems to new developers - what each subsystem does, why it does what
it does, where is the code, and so on. I am facing these problems every
day as a seasoned developer - I can't even imagine what our new developers
face when trying to understand a subsystem they are not yet familiar with.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20180920131103.20590-1-nyh@scylladb.com>
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