With this change the scraping caches series references and only
allocates label sets if it has to retrieve a new reference.
pkg/textparse is used to do the conditional parsing and reduce
allocations from 900B/sample to 0 in the general case.
0 is considered an invalid interval by time.NewTicker() and will cause a
panic if control reaches that point. Given the vagaries of timekeeping,
this may occasionally happen and make this test unstable.
This commit removes the scrapeConfig entirely from Target.
All identity defining parameters are thus immutable now and the mutex
can be removed..
Target identity is now correctly defined by the labels and the full URL.
This in particular includes URL parameters that are not specified in the
label set.
Fingerprint is also removed from hash to remove an unnecessary tight coupling
to the common/model package.
This commit changes the scraper interface to accept a timestamp
so the reported timestamp by the caller and the timestamp
attached to samples does not differ.
Fabian Reinartz
Tobias Schmidt
Anders Daljord Morken
Julius Volz