Mailing List Archive

Tendril shutdown
Hello,

If you don’t use tendril.wikimedia.org or dbtree.wikimedia.org, feel free
to ignore this message.

As of today, tendril is now retired and the main page is replaced with a
list of replacement for different services tendril used to provide:


-

For checking out our dbtree and replication data:
-

if you are in the NDA LDAP group, use Orchestrator
<https://orchestrator.wikimedia.org>
-

otherwise, use the information page <https://noc.wikimedia.org/db.php>
on noc.wikimedia.org. For more detail you can also check eqiad.json
<https://noc.wikimedia.org/dbconfig/eqiad.json> or codfw.json
<https://noc.wikimedia.org/dbconfig/codfw.json>
-

If you are looking for slow queries log, go to slow queries dashboard
<https://logstash.wikimedia.org/app/dashboards#/view/43fcccd0-4df5-11ec-81e9-e1226573bad4>
using our standard observability platform (logstash) (NDA required)


Tendril has been a great tool for us during the years, but unfortunately it
is impossible to maintain with modern MariaDB versions (it uses TokuDB,
which is no longer available on MariaDB after 10.1 and needs to be compiled
separately) nor its webservice is compatible with modern php versions. Its
database is still running on Stretch and on MariaDB 10.1 (which has not
been supported for a year already) and it is having serious scalability
issues. This would unblock us from removing a lot of legacy home-brew craft
and replace them with more modern toolings such as orchestrator
<https://orchestrator.wikimedia.org>.

Orchestrator has been in place for a few months now, and provides us with a
great way to see and (in the future) manage replication topologies. For now
we are using it only for visualization purposes but in the future we’d like
it to also help us to handle replication changes (it can be done from the
UI or via CLI) and recover topologies automatically if they fail and
involve masters or intermediate masters.

The slow queries dashboard
<https://logstash.wikimedia.org/app/dashboards#/view/43fcccd0-4df5-11ec-81e9-e1226573bad4>
in logstash offer multiple advantages over tendril. You can set the
threshold to see slow queries that took longer to run. You can filter out
code paths you’re not interested in or zoom in to relevenet code paths. You
can limit it to write queries or read queries only. Also, it provides id of
the request making the slow query, so you can cross check it with the rest
of logstash or hadoop to identify problematic behavior.

If you need it for the transition period, you can still access it in
tendril-legacy.wikimedia.org. But it will be shut down in a month. You can
follow the work of shutting down tendril in
https://phabricator.wikimedia.org/T297605.

Thank you.