Stephen Bates <sbates@xxxxxxxxxxxx> writes: > Hi Jeff > >> Can you expand on the use case? Why is the number of events a useful >> parameter? >> >> Thanks, >> Jeff > > I am working on tying blktrace into a prometheus exporter so I can > monitor block-level activity across a fleet of storage servers. I > don't want to overload either the storage server CPUs or the exporter > itself when the server is under high load so I want to avoid using the > time-based argument for blktrace. > > If I have access to an events based option I can run this knowing that > in high-load situations I will not be capturing many, many IO and > perhaps slowing down the server in the process. > > Does that make sense? Yes, thanks for the clarification. Originally I thought you might be using the number of events as a proxy for the size of data collected. I'm still not sure how a user would reason about how many events is too many (or enough), but that's a not a problem for blktrace to figure out. I'll reply to the patch with my comments. Cheers, Jeff
