graphite-dev team mailing list archive

[chrismd <question169504@xxxxxxxxxxxxxxxxxxxxx>]

Question #169504 on Graphite changed:
https://answers.launchpad.net/graphite/+question/169504

    Status: Open => Answered

chrismd proposed the following answer:
Yes federated storage is still a supported feature. The second part of
your question though, "Specifically, I would like to know if the same
metric could reside on various backend servers yet still pull the needed
data from all severs to plot the graph" has a more nuanced answer.

There are two database libraries I've written for Graphite: whisper and
ceres. Whisper is the default in all releases so far and is the only
thing supported on trunk currently. Ceres was added in a new branch that
is very soon merging into trunk and will be available as an option in
the 1.0 release (which I'm planning on putting out by the end of this
year).

Whisper lets you do federated storage in a more restricted way than
Ceres does. With whisper, you can distribute your metrics across many
servers but metrics cannot easily move a metric from one server to
another. Also if you add or remove a server from your cluster you have
to do some manual reconfiguration and possibly moving of data files to
make it a clean transition. Federated storage is possible with whisper
but for these reasons it can sometimes be a pain in the ass.

With Ceres none of this is necessary, you can add/remove servers at will
and not worry about configurations. It is used in production by a few
companies but it requires a lot of effort to setup because it is still
not documented and has a few significant differences from whisper and
currently requires more setup.

Basically, you can:
a) use federated storage with whisper and deal with the hassles I mentioned above
b) learn how to use ceres and deal with the lack of documentation
c) learn how to use ceres and help write the documentation to aid everyone else (my personal favorite)
d) wait until ceres becomes better documented

If you want to take a stab at trying Ceres let me know, I can give you
some pointers.

-- 
You received this question notification because you are a member of
graphite-dev, which is an answer contact for Graphite.