maobo wrote: > Hi,all > Yes, Raid10 read balance is the shortest position time first and > considering the sequential access condition. But its performance is > really poor from my test than raid0. Single-stream write performance of raid0, raid1 and raid10 should be of similar level (with raid5 and raid6 things are different) -- in all 3 cases, it should be near the write speed of a single drive. The only possible problematic cases is when you've some "unlucky" hardware which does not permit writing into two drives in parallel - in which case raid1 and raid10 write speed should be less than to raid0 and single drive. But even ol'good IDE drives/controllers, even if two disks are on the same channel, permits parallel writes. Modern SATA and SCSI/SAS should be no problem - hopefully, modulo (theoretically) some very cheap lame controllers. > I think this is the process flow raid10 influence. But RAID0 is so > simple and performed very well! > From this point that striping is better than mirroring! RAID10 is > stipe+mirror. But for write condition it performed really bad than RAID0. > Isn't it? No it's not. When the hardware (and drivers) is sane anyway. Also, "speed" is a very objective thing, so to say - it very much depends on the workload. /mjt - 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
