dgwynne

At work we tunnel WoL payloads inside DHCP packets (https://github.com/eait-itig/wolod) so we can use the DHCP relays on the edge network to push the packets out for us. The bootp procotol has a handy flag that indicates whether the last dhcp relay should broadcast or unicast the message being relayed, which is very useful in this situation.

I can't think of a reason not to ship DWARF except that it is big. Is there any other reason?

CTF is obviously less capable than DWARF, but it is small enough to ship by default and in my experience it is Good Enough(tm) for most debugging needs.

Solaris developed another solution, specifically CTF (Compressed Type Format). CTF stores data types and function signatures rather than full debug info, and is therefore much smaller than the DWARF information it is derived from.

The entire Solaris system is built with CTF enabled, which is used to support their debuggers and dtrace. Other systems have adopted it too. OpenBSD is moving to use CTF, and has enabled it's use in the kernels and debuggers on some architecture.

To get a sense of the size difference, DWARF information for a sparc64 kernel is about 27 megabytes. The CTF information derived from it is 473 kilobytes.

This is also discussed in section 4 of Jeff Bonwick s 1994 paper "The Slab Allocator: An Object-Caching Kernel Memory Allocator".