On Tue, Dec 12, 2017 at 01:35:13PM +0200, Nikolay Borisov wrote: > On 11.12.2017 18:00, Scott Bauer wrote: > > + As an example: > > + > > + Intel NVMe drives contain two cores on the physical device. > > + Each core of the drive has segregated access to its LBA range. > > + The current LBA model has a RAID 0 128k stripe across the two cores: > > + > > + Core 0: Core 1: > > + __________ __________ > > + | LBA 511| | LBA 768| > > + | LBA 0 | | LBA 256| > > + ⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻ ⎻⎻⎻⎻⎻⎻⎻⎻⎻⎻ > > If it's 128k stripe shouldn't it be LBAs 0/256 on core0 and LBAs 128/511 > on core1? Ah, this device's makers call the "stripe" size what should be called "chunk". This device has a 128k chunk per core with two cores, so the full stripe is 256k. The above should have core 0 owning LBA 512 rather than 511 (assuming 512b LBA format). -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
