[squid-users] SIGBUS attempting to use rock

[Antonio SJ Musumeci]

I'm sending this out for those that might run into this in the future.

After a lot of tinkering and turning on full debug I realized the reason 
rock was failing for me in my container was due to the small default SHM 
size allocated by Docker. Increasing the SHM size with `--shm-size` 
fixed the issue.

It'd be significantly more helpful if the Squid reported precisely what 
the issue and exited gracefully rather than SIGBUS'ing.