currently the whole SmartShunt data structure is copied to the
BatteryStats instance in every loop, even though the data cannot
possibly have changed. this is quite an expensive task to do in every
loop. this change tracks the last update timestamp and only does the
copy operation if an actual updated data structure was received from
the smart shunt.
the TaskScheduler runs in the context of a FreeRTOS thread/task. there
are other such threads (MQTT client and web server in particular). to
allow changing TaskScheduler task properties from different threads, we
need to enable the use of a mutex to protect the TaskScheduler.
this change adds the values of ESP.gteMaxAllocHeap() and
ESP.getMinFreeHead() to the prometheus metrics and the system
information object. the web UI uses these values to diplay the size of
the largest free contiguous block, calculate a rough estimate for the
level of fragmentation, and the maximum usage of heap memory since boot
in absolute and relative amounts.
this change utilizes some of the features from library "frozen", which
was included upstream for the grid profile parser. to improve code
maintainability, a couple of std::maps mapping strings to values or the
other way around were introduced in OpenDTU-OnBattery-specific code at
the expense of some flash and computing overhead.
library "frozen" offers constexpr versions of map and string, which
saves initialization code and offers slightly faster lookups. this
brings the binary size down by ~25kB and should provide a small
performance improvement at runtime.
this battery provider implementation subscribes to a user-configurable
MQTT topic to retrieve the battery SoC value. the value is not
re-published under a different topic. there is no card created in the
web app's live view, since the SoC is already part of the totals at the
top of the live view. that is the only info this battery provider
implements.
closes#293.
relates to #581.
MQTT message callbacks are executed in the MQTT thread context. when
processing topics that control the DPL, we must avoid executing methods
that are not thread-safe. this change binds the methods to be called to
the respective parameters and executes them in the TaskScheduler
context, such that they no longer need to be thread-safe.