On 11/1/25 06:53, Bart Van Assche wrote: > On 10/30/25 11:13 PM, Damien Le Moal wrote: >> Introduce the function blkdev_report_zones_cached() to provide a fast >> report zone built using the blkdev_get_zone_info() function, which gets >> zone information from a disk zones_cond array or zone write plugs. >> For a large capacity SMR drive, such fast report zone can be completed >> in a few millioseconds compared to several seconds completion times >> when the report zone is obtained from the device. > > millioseconds -> milliseconds > > Does retrieving the cached zone information really require multiple > milliseconds instead of only a few microseconds?
There are over 100,000 zones on large capacity SMR HDDs. And I have models with smaller zone size that have over 200,000 zones. So yes, a few milliseconds are needed on normal (read not super fast) CPUs. -- Damien Le Moal Western Digital Research
