Btw, I think these could also easily map to DSM field in the NVMe write command, except that these unfortunately mix in read information as well. > + __REQ_WRITE_SHORT, /* short life time write */ -> Frequent writes and infrequent reads to the LBA range indicated. or -> Frequent writes and frequent reads to the LBA range indicated. > + __REQ_WRITE_MEDIUM, /* medium life time write */ -> Typical number of reads and writes expected for this LBA range. > + __REQ_WRITE_LONG, /* long life time write */ -> Infrequent writes and infrequent reads to the LBA range indicated. or -> Infrequent writes and frequent reads to the LBA range indicated. > + __REQ_WRITE_EXTREME, /* extremely long life time write */ -> One time write. E.g. command is due to virus scan, backup, file copy, or archive.