On 11/25/16 8:50 AM, Dave Hall wrote: >> mkfs.xfs will do this setup automatically on software raid and any >> block device that exports the necessary information to set it up. >> In general, it's only older/cheaper hardware RAID that you have to >> worry about this anymore. >> > So how do we know for sure? Is there a way that we can be sure that > the hardware RAID has exported this information? If you run mkfs.xfs and it shows stripe geometry in the stdout info, then it detected stripe geometry. Otherwise you can use lsblk -t to print the advertised topology: # lsblk -t /dev/md121 NAME ALIGNMENT MIN-IO OPT-IO PHY-SEC LOG-SEC ROTA SCHED RQ-SIZE RA WSAME md121 0 512 0 512 512 1 128 128 0B min io size is the stripe unit, opt IO size is the stripe width. (in the above case there is no stripe geometry; 512-byte min IO and 0 optimal IO is uninteresting). > In lieu of this, is > there a solid way to deduce or test for correct alignment? If the device itself doesn't advertise a stripe geometry and you think it has one, you'll need to look at the device settings, bios, documentation, configuration, or whatever else to work it out on your own, and then specify that manually on the mkfs.xfs commandline. -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
