added readout-defaults

Author: sy-c

doc/configurationParameters.md

@@ -1,5 +1,36 @@
 # Readout configuration parameters reference
 
+This document describes all the configuration parameters that can be set in readout.
+
+Some parameters control the behavior of readout as soon as it starts, and valid for the lifetime of the process. (1)
+
+Other parameters (2) are set whenever the control state-machine receives the CONFIGURE command (or shortly after startup when running o2-readout-exe outside from the ECS workflow, typically from the command line) and until the RESET command.
+The corresponding parameters usually come from a local file or from a central reposity, as provided by the O2 system.
+They can be reloaded several time during the lifetime of the process.
+
+
+# Readout defaults (1)
+
+These are defined in local file `/etc/o2.d/readout-default.cfg`, which is loaded on `o2-readout-exe` startup (if file exists). They are valid for the lifetime of the o2-readout-exe process. There is usually no need for users to edit these settings. The file format is '.ini' style, with `[sections]` and `key=value` pairs.
+
+Following table describe the parameters of the `[readout]` section.
+
+| Parameter name  | Type | Default value | Description |
+|--|--|--|--|
+
+| memLock | int | 0 | Defines the memory swapping policy. If set, all readout memory is locked in RAM with mlockall() |
+| readoutExe | string | | If set, overwrites the current running executable with the one at given path. Used for tests. |
+| readoutConfig | string | | If set with readoutExe, launch the new exe with this parameter as argument. Used for tests. |
+| statsPublishAddress | string | | If set, address where to publish readout stats, eg "tcp://127.0.0.1:6008". Connect to this service with o2-readout-monitor. |
+| statsPublishInterval | string | | If set, interval for readout stats publish, in seconds. |
+| db | string | | If set, defines connection parameters to a MySQL database in the form 'user:password@host/dbname'. Runtime statistics are stored in a table. Structure can be created with o2-readout-admin-db. |
+| customCommandsEnabled | int | 0 | If set, custom commands are enabled, i.e. launching external scripts at some specific state transitions. See customCommands keyword below. |
+| membanksMonitorPath | string | | Path to memory banks monitor output (a local file FIFO, to be connected with o2-readout-monitor). |
+| membanksMonitorRate | double | 0 | Rate (in Hertz) at which to publish memory status. |
+
+
+# Readout configuration file (2)
+
 ## Sections
 The readout configuration is split in different sections. Some sections have a unique instance (single name), some may have multiple instances (prefix-[instance name], shown as prefix-\* in this document).