Hi, I have no idea why does raid0_run() in raid0.c use blk_queue_max_hw_sectors() to set max_hw_sectors as the chunk size, but the other raid types doesn't? What's the purpose to limit the max_hw_sectors in raid0? Is it related to the source code logic issue or the performance issue? Besides, I have an interesting observation. If I remove all the following queue limitation codes in raid0_run() of raid0.c, the block size in iostat is still the same as chunk size even the input block size is much larger than the chunk size. Why??? - blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors); - blk_queue_max_write_same_sectors(mddev->queue, mddev->chunk_sectors); + //blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors); + //blk_queue_max_write_same_sectors(mddev->queue, mddev->chunk_sectors); - blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9); - blk_queue_io_opt(mddev->queue, - (mddev->chunk_sectors << 9) * mddev->raid_disks); + //blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9); + /*blk_queue_io_opt(mddev->queue, + (mddev->chunk_sectors << 9) * mddev->raid_disks);*/ -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
