GuaranteedSafepointInterval clarification

[Vitaly Davidovich]

Hi all,

Could someone explain the reasoning for 1s being the default value here? It
seems quite low given the types of things it appears to handle (monitor
deflation, inline cache updates, symbol table rehashing, nmethod sweeping,
etc).

Also, I do not always see these safepoints initiated every ~1s.  Looking at
SafepointSynchronize::is_cleanup_needed(), this seems to kick in only when
InlineCacheBuffer has some entries.  Is that right? This code will only run
if compiler has updated inline caches?

Why is GuaranteedSafepointInterval a diagnostic option and not full product
like, say, a GC tuning option?

Finally, when tracing safepoint stats, these cleanup ones appear as "no vm
operation" in the output -- it seems like it would be nicer to print
something like "GuaranteedSafepointInterval" or something to that effect.

Thanks