Pool
Device Pool is easily extendable by means of controller plugins. Device Pool
discovers them in directories configurable via
pool path attribute. In case Sardana is used with
Tango this configuration is accessible via the PoolPath
Pool device property.
Your controller plugins may need to access to third party Python modules. One
can configure the directory where to look for them via
python path attribute. In case Sardana is
used with Tango this configuration is accessible via the PythonPath
Pool device property.
Device Pool implements a controlled way of performing
Motion and Acquisition.
These actions consists of performing a high frequency polling loops
over the involved elements in order to control and update the
states and the principal attributes i.e. Position for
a motor or Value for an experimental channel
e.g. Counter/timer. The default
frequency of these polling loops can be controlled with the following
Pool device properties:
MotionLoop_SleepTime- sleep time in the motion loop between the state reads in ms (default: 10 ms)MotionLoop_StatesPerPosition- number of state reads done before doing a position read in the motion loop (default: 10)AcqLoop_SleepTime- sleep time in the acquisition loop between the state queries in ms (default: 10 ms)AcqLoop_StatesPerValue- number of state reads done before doing a value read in the acquisition loop (default: 10)
Device Pool integrates natively with the
Elastic Stack and may send logs to the a Logstash
instance. In case Sardana is used with Tango this configuration is
accessible via the LogstashHost and LogstashPort
Pool device properties.
You can use the intermediate SQLite cache database configured with
LogstashCacheDbPath property, however this is discouraged due to logging
performance problems.
Todo
Document RemoteLog, DriftCorrection, InstrumentList