This is visible in the embedded binary viewer: https://play.clickhouse.com/binary?user=binary&zoom=0&x=1620...

(It shows only about 500 MB of machine code, and the rest of the gigabytes are debug info.)

Very typical for anything with CUDA (they tend to compile everything for 10 different architectures times hundreds of template kernel parameters).

Not sure about ClickHouse though.

#include <iostream>

Heavy use of C++ templates can significantly increase the binary size. Same for the heavy use of generated code (e.g. protocol buffers etc.).

ClickHouse is a completely stand-alone binary that doesnt rely on any linked libraries. Not sure how much of this explains the large binary size, though.