Open Stack

On Mon, May 09 2016, Thomas Herve wrote:


[…]

> Using DLM
> ----------------
>
> We managed to not talk about ZooKeeper too much :). We want to remove
> the database locks that we have and use tooz instead. The key is to
> provide a nice upgrade path, so starting with the locks use for
> convergence seems easier. If it turns out to be painless, we'll move
> the stack locks from the legacy engine as well.

I don't know what stack lock so my apologies if I'm saying anything
wrong.

There might be a nice upgrade path solution, which is to use your
database as the lock manager. Tooz provides locking primitive against
MySQL and PostgreSQL with their respective driver.

We do that by default in Gnocchi. It offers a very nice and simple
"works by default": Gnocchi picks the database URL and pass it to Tooz,
so we have a DLM "for free".

Then, bigger deployments can tweak the Tooz URL to make it point to
something more robust (ZooKeeper, etcd…).

My 2c,

-- 
Julien Danjou
;; Free Software hacker
;; https://julien.danjou.info
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