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Maybe you can actually spell this out? >> >> Please just tell me what you would like to see, and I will copy verbatim. > > Probably just what I just wrote. Unless Martin can come up with > better language. There is no reliable way for the SCSI subsystem to determine whether a device supports a WRITE SAME operation without actually performing a write to media. As a result, write_zeroes is enabled by default and will be disabled if a zeroing operation subsequently fails. This means that this queue limit is likely to change at runtime. Something like that, perhaps? -- Martin K. Petersen Oracle Linux Engineering