October 2022

Best Practices: Tracking Battery Life

Two of the most important IoT reliability metrics are the expected and the actual battery life for devices. Understanding and predicting trends for battery life and detecting regressions with thousands to millions of devices in the field is a challenging problem that Memfault recently published advice and product improvements for.

The combination of metric charts, device timeline, and the recently added documentation with code samples help with understanding battery life of MCU, Linux or Android devices.

General

• Added: Documentation of best practices for battery life tracking
• Added: Timezone picker for selecting custom timezones
• Improved: UI glitches and improvements (More readable timestamps under Device Details → Log Files, error prompt to prevent misconfigured Issue Charts)
• Fixed: Introduction pages linking to themselves on Memfault Docs
• Fixed: Timeouts when loading the Received Traces charts on the Dashboard
• Fixed: Pending software version of a device was not updated after configuring a new deployment
• Fixed: Empty metric charts when a formerly non-timeseries metric is used in the chart

MCU

• SDK version 0.33.5 was released. Some highlights:
  • Added: Example Zephyr application targeting the QEMU board
  • Added: Support for ESP-IDF v4.2.3
  • Added: Configuration option for setting the ESP-IDF HTTP client timeout value
  • Improved: nRF9160 example application to build and run correctly with nRF-Connect SDK v2.1.0
  • Fixed: Compilation for the ESP32-S3

Android

• Added: Creation of kernel oops traces from last_kmsg
• Improved: OTA link expiry window increased to 6hr (previously 1hr) for more reliable downloads on slow internet connections
• SDK version 4.3.0 was released. Some highlights:
  • Added: logging mode “continuous” as alternative capture strategy on the device
  • Added: On-device scrubbing of tombstone files
  • Improved: Built-in metrics for storage (changed from storage.primary. to storage.data.)
  • Fixed: Potential OTA app crash due to a race condition

Linux

• Added: Documentation of when reads and writes happen to Linux SDK data_dir
• We did not publish a new version of the Memfault Linux SDK in October.