On Wednesday June 11, hubskml@xxxxxxx wrote: > > By the way and FYI, with my configuration, all disks on the same > controller, internal bitmap, v1 superblock, ... the initial RAID-5 > synchronization duration is the same whether I'm using the option > --force or not. For this to be a valid test, you need to fill one drive up with garbage to ensure that a resync is no a no-op. If you don't use the "--force" option, then the recovery process will read from N-1 drives and write to 1 drive, all completely sequentially so it will go at a predictable speed. When you use "--force" it will read from N drive and check parity. When it finds an error it will re-write that parity block. So if the parity blocks happen to be all correct (as probably was the case in your experiment), it will run nice and fast. If the parity blocks happen to all be wrong (as is likely when first creating an array on drives that weren't an array before) it will be much slower. NeilBrown -- 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
