Support embedded devices with limited resources

[v0y4g3r]

Time-series storage and computing is also needed in edge computing scenarios. We need to optimize GreptimeDB for those resource limited devices. For example, reducing memory footprint, employing more lightweight runtime, some flash-friendly flush&compaction strategies and even supporting no-std.

There're some tasks to archieve this goal:

• The first step towords this goal is to support cross compilation to these platforms to continously deliver platform-specify binaries.
• Baseline benchmark to get a rough stats of how GreptimeDB performs on these platforms.
• Reduce CPU and memory footprint according to benchmark results to see what we can do in the furture.

[v0y4g3r]

The first attemp of cross compilation is done by #1802.