Hi all, When using fio configuration below.. [global] ioengine=libaio direct=1 runtime=600 bs=32k iodepth=8 rw=randrw rwmixread=80 percentage_random=100,0 [drive1] filename=/dev/sda I am expecting to see 80% reads, 20% writes where all reads are random and all writes are sequential. I captured a bus trace of traffic to the disk and the bus trace reflected as much with one issue. The write commands are essentially random. Each write begins at a new random LBA. If 2 or more writes occur in a row, the LBA's are sequential based on the block size BUT I feel the heart of this feature would be to emulate a large file write during random access. With that in mind would it be possible for sequential reads or writes within mixed sequential/random workload to remember the last LBA accessed? In this scenario the writes would still only take up 20% of the workload but when a write did occur it should be the next sequential step from the last write. Snippet from the bus trace for reference Command LBA Read FPDMA Queued: 19F3F818 Read FPDMA Queued: 1CBE2740 Write FPDMA Queued: 24E35198 Write FPDMA Queued: 24E351A0 Read FPDMA Queued: 115A9E10 Write FPDMA Queued: A3C1968 Read FPDMA Queued: 20B89488 Write FPDMA Queued: 336EE0D0 Write FPDMA Queued: 336EE0D8 Let me know what you think, this feature may be working as intended but it seemed off to me. Thanks, Stephen "Nick" Nichols Western Digital Enterprise Test Development -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
