strace

That is you can't strace a program that uses strace (or more precisely, the ptrace syscall).

Of course, strace doesn't exist in vacuum, it changes the way your code executes.

Buildcache uses strace rather than parsing command line arguments of the compiler to save and reuse compilation results, speedin up subsequent builds.

You can often find substantial bottlenecks in applications in about 10 seconds by attaching strace and look for stupid amounts of syscalls.

In an isolated environment, run it with strace -o nasties.txt or something similar.

Great book on debugging issues on Linux \w strace, gdb, core dumps, etc.

Agreed - from the name and the mention of strace, I immediately got how it worked.

Now I can't login to the production server in order to strace the process to figure out why production is misbehaving.

If your adversaries are on your box while you operate your vault, then you have already lost because they will also have keyloggers, strace, etc.

When I looked into why, it's basically the time it takes to print and read from strace - printing to stdout every time there is a syscall is obviously very slow.

When implementing pthread_create(3), the return value for the parent is still an integer value which is unique to the thread, and which strace uses as if it were a PID when it's tracing down the system calls of individual threads in separate files, which strace can do because it's awesome.

Really learn how to use Strace -- you should know what the difference is between a system call and a library call and be familiar with many of the common system calls you see in the output of that.

The "trick" here is using strace to figure out the complete set of inputs to the (assumed to be) idempotent compilation steps.

Nice, but a problem with this approach is that strace is not "re-entrant".

To track down dependencies, "strace" is your friend.

While this is interesting, for every Ruby app I've worked on where startup times became an issue, the culprit was trivially found with "strace" to be caused by excessive pollution of the load path to the point where pointless stat-calls totally dominates load time.