[LLVMdev] multithreaded performance disaster with -fprofile-instr-generate (contention on profile counters)

[Duncan P. N. Exon Smith]

On 2014-Apr-17, at 10:38, Xinliang David Li <xinliangli at gmail.com> wrote:

> 
> Another idea is to use stack local counters per function -- synced up with global counters on entry and exit. the problem with it is for deeply recursive calls, stack pressure can be too high.

I think they'd need to be synced with global counters before function
calls as well, since any function call can call "exit()".