Am Mittwoch, 9. Mai 2012, 22:01:49 schrieb Daniel Pocock: > There is various information about > - enterprise-class drives (either SAS or just enterprise SATA) > - the SCSI/SAS protocols themselves vs SATA > having more advanced features (e.g. for dealing with error conditions) > than the average block device > > For example, Adaptec recommends that such drives will work better with > their hardware RAID cards: […] > - for someone using SAS or enterprise SATA drives with Linux, I > understand btrfs gives the extra benefit of checksums, are there any > other specific benefits over using mdadm or dmraid? I think I can answer this one. Most important advantage I think is BTRFS is aware of which blocks of the RAID are in use and need to be synced: - Instant initialization of RAID regardless of size (unless at some capacity mkfs.btrfs needs more time) - Rebuild after disk failure or disk replace will only copy *used* blocks Scrubbing can repair from good disk if RAID with redundancy, but SoftRAID should be able to do this as well. But also for scrubbing: BTRFS only check and repairs used blocks. Another advantage in the future – not yet possible AFAIK: - Different RAID levels on same filesystem yet different subvolumes, more flexibility as subvolumes are dynamically allocated, instead of statically sized Ciao, Martin -- Martin Steigerwald Consultant / Trainer teamix GmbH Südwestpark 43 90449 Nürnberg fon: +49 911 30999 55 fax: +49 911 30999 99 mail: martin.steigerwald@xxxxxxxxx web: http://www.teamix.de blog: http://blog.teamix.de Amtsgericht Nürnberg, HRB 18320 Geschäftsführer: Oliver Kügow, Richard Müller ** JETZT ANMELDEN – teamix TechDemo - 23.07.2014 - http://www.teamix.de/techdemo ** -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
