After 1.5.0 earlier in the year, Prometheus 1.6.1 is now out. There’s a plethora of changes, so let’s dive in.
The biggest change is to how memory is managed. The -storage.local.memory-chunks and -storage.local.max-chunks-to-persist flags have been replaced by -storage.local.target-heap-size. Prometheus will attempt to keep the heap at the given size in bytes. For various technical reasons, actual memory usage will be higher so leave a buffer on top of this. Setting this flag to 2/3 of how much RAM you’d like to use should be safe.
The GOGC environment variable has been defaulted to 40, rather than its default of 100. This will reduce memory usage, at the cost of some additional CPU.
A feature of major note is that experimental remote read support has been added, allowing the read back of data from long term storage and other systems.
Read more at CNCF
