Try Go 1.21 PGO

[poszu]

The Profile Guided Optimization (PGO) is officially available since go 1.21 https://go.dev/blog/go1.21.

Steps:

• gather profile data on one of the bare-metal poets (is-poet could be used),
• rebuild with PGO
• compare the POSW performance
• if performance is improved, then incorporate in release build in CI