Pico_speed_O3_compile.txt

In
C:\Users\guido\AppData\Local\Arduino15\packages\rp2040\hardware\rp2040\1.9.5\platform.txt
(to find the file replace guido with your username )

-Os
====

compiler.flags=-Os -march=armv6-m -mcpu=cortex-m0plus -mthumb -ffunction-sections -fdata-sections -fno-exceptions

Sketch uses 114400 bytes (5%) of program storage space. Maximum is 2093056 bytes.
Global variables use 78800 bytes (30%) of dynamic memory, leaving 183344 bytes for local variables. Maximum is 262144 bytes.

-O3 (34.78% more speed while using 250Mhz)
==========================================

compiler.flags=-O3 -march=armv6-m -mcpu=cortex-m0plus -mthumb -ffunction-sections -fdata-sections -fno-exceptions

Sketch uses 138784 bytes (6%) of program storage space. Maximum is 2093056 bytes.
Global variables use 78772 bytes (30%) of dynamic memory, leaving 183372 bytes for local variables. Maximum is 262144 bytes.