Dear list, concerning RAIDs with Desktop class drives it'd be good to know if there is any kernel-timeout-value which states, how long a diskdrive may take to process a command. If it doesn't respond in-time I've seen in my logs and with many disks that the sg-eh becomes active resetting the bus. So somewhere there needs to be such a timeout. The question is: can this timeout-value be found somewhere in the sysfs? If "yes" where? If "no", can it be exported? Suggestions for the maximum of this timeout-value: I've read in multiple places that the internal error correction of desktop-class drives can even take more than 2 minutes to complete. But another much bigger value can be taken directly out of the IDENTIFY_DEVICE_STRUCTURE, word 89, which states how long a SECURITY_ERASE_UNIT command takes approximately (in minutes-see ATA8-ACS, table 32 for the exact meaning of the value). A in some cases even longer time can be found in word 90 (time estimate for enhanced security erase unit, table 33). I know for sure that this command should not be issued from linux - at least not at this state of libata. I've done it twice on two different Samsung HD103UJ drives to "securely erase customer data". While executing the command libata made the PassThru command fail within a minute and according to syslog it unsuccessfully tried to reset the drive. The results were (after letting the drives run for about the indicated 3 hours): one drive broke completely, it was never again recognized on any computer, the other drive was recognized though, but did not operate properly anymore. Any comments and hints are very welcome. All the best, Stefan -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
