This ensures we don't end up wasting resources by tracking method calls
that only take a few microseconds. By default the threshold is 10
milliseconds but this can be changed using the gitlab.yml configuration
file.
This adds the ability to write application metrics (e.g. SQL timings) to
InfluxDB. These metrics can in turn be visualized using Grafana, or
really anything else that can read from InfluxDB. These metrics can be
used to track application performance over time, between different Ruby
versions, different GitLab versions, etc.
== Transaction Metrics
Currently the following is tracked on a per transaction basis (a
transaction is a Rails request or a single Sidekiq job):
* Timings per query along with the raw (obfuscated) SQL and information
about what file the query originated from.
* Timings per view along with the path of the view and information about
what file triggered the rendering process.
* The duration of a request itself along with the controller/worker
class and method name.
* The duration of any instrumented method calls (more below).
== Sampled Metrics
Certain metrics can't be directly associated with a transaction. For
example, a process' total memory usage is unrelated to any running
transactions. While a transaction can result in the memory usage going
up there's no accurate way to determine what transaction is to blame,
this becomes especially problematic in multi-threaded environments.
To solve this problem there's a separate thread that takes samples at a
fixed interval. This thread (using the class Gitlab::Metrics::Sampler)
currently tracks the following:
* The process' total memory usage.
* The number of file descriptors opened by the process.
* The amount of Ruby objects (using ObjectSpace.count_objects).
* GC statistics such as timings, heap slots, etc.
The default/current interval is 15 seconds, any smaller interval might
put too much pressure on InfluxDB (especially when running dozens of
processes).
== Method Instrumentation
While currently not yet used methods can be instrumented to track how
long they take to run. Unlike the likes of New Relic this doesn't
require modifying the source code (e.g. including modules), it all
happens from the outside. For example, to track `User.by_login` we'd add
the following code somewhere in an initializer:
Gitlab::Metrics::Instrumentation.
instrument_method(User, :by_login)
to instead instrument an instance method:
Gitlab::Metrics::Instrumentation.
instrument_instance_method(User, :save)
Instrumentation for either all public model methods or a few crucial
ones will be added in the near future, I simply haven't gotten to doing
so just yet.
== Configuration
By default metrics are disabled. This means users don't have to bother
setting anything up if they don't want to. Metrics can be enabled by
editing one's gitlab.yml configuration file (see
config/gitlab.yml.example for example settings).
== Writing Data To InfluxDB
Because InfluxDB is still a fairly young product I expect the worse.
Data loss, unexpected reboots, the database not responding, you name it.
Because of this data is _not_ written to InfluxDB directly, instead it's
queued and processed by Sidekiq. This ensures that users won't notice
anything when InfluxDB is giving trouble.
The metrics worker can be started in a standalone manner as following:
bundle exec sidekiq -q metrics
The corresponding class is called MetricsWorker.
This adds support for AWS S3 SSE with S3 managed keys, this means the
data is encrypted at rest and the encryption is handled transparently to
the end user as well as in the AWS Console. This is optional and not
required to make S3 uploads work.
Until now, a user needed to first sign in with his LDAP identity and then manually
link his/her account with an omniauth identity from their profile.
Only when this is done can the user authenticate with the omniauth provider and at
the same time benefit from the LDAP integration (HTTPS authentication with LDAP
username/password and in EE: LDAP groups, SSH keys etc.).
This feature automates the process by looking up a corresponding LDAP person when a
user connects with omniauth for the first time and then automatically linking the LDAP
and omniauth identities (of course, like the existing allow_single_sign_on setting,
this is meant to be used with trusted omniauth providers).
The result is identical to a manual account link.
Add config initializers for other omniauth settings.
Yorick Peterse
Douwe Maan
Kamil Trzcinski
Marin Jankovski
Dmitriy Zaporozhets
Jacob Vosmaer
Paul Beattie
Robert Speicher
Sytse Sijbrandij
Sameer Naik
Valery Sizov
Ted Strzalkowski
Robert Speicher
Jeroen Nijhof
Alex Lossent
Jakub Jirutka
Stan Hu
Achilleas Pipinellis
win32
Vinnie Okada