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Automated Tiered Storage Coming to Desktops?
roj3 writes "Tiered storage has been the scourge of administrators because the vendors tell us to hold meetings with all departments and then classify data to storage tier based on its type or relative importance. eWeek has a story about a new approach to tiered storage — sorting it all by usage patterns. Regularly used data goes on high-performance storage, idle data goes on slower/cheaper storage. Volumes and files even span several types of drives or RAID levels. Is automated tiered storage headed to desktops?"
Automatic tiered storage is definitely coming, but probably not in the form of multiple disks that run at different speeds or RAID levels.
Microsoft announced a while back that Windows Vista would support three technologies designed to improve disk speed called SuperFetch, ReadyBoost, and ReadyDrive. SuperFetch is simply a way of preloading applications and data when the OS anticipates that you'll be loading those soon.
ReadyBoost and ReadyDrive both utilize persistent memory caches to speed up access to the disk.
ReadyBoost treats normal USB keys and flash disks like temporary caching locations for data from the disk.
ReadyDrive is essentially the term Microsoft uses to described their support for hybrid hard drives, which are disks that have a built in flash memory module that's used as a persistent cache.
Not only do hybrid disks dramatically increase performance, but they also result in huge power savings for mobile devices like laptops and media players.
No. Absent other data, it only denotes frequency of use, period. Playboy.com gets more hits than the general ledger webapp if you unblock your company firewall, but the general ledger is more important to the company.
There is actually very little correlation between what the average user wants and what s/he needs, as is empirically obvious. If the image from the "fly-fishing.com" website that they've set to come up as their background image every morning fails to load, they can still work, but if the once-a-year corporate audit checklist gets put on slow, old storage and then gets lost in a hardware failure, the company stock price may flutter and certainly heads will roll in the corporate IS department.
I don't think that word means what you think it means.
It was called HSM, (Hierarchical Storage Management) it ran on IBM's MVS on mainframes, and it moved your less-used data to cheaper storage, in several stages. IIRC, the first stage was just compression on a different disk, the second stage was a tapes in a jukebox-type thing, and the third stage was tapes that an operator fetched and loaded. Somewhere way back there, data never used for 5 years fell off the end of the belt, but you got warned, first.
The day after vacation, when you kept getting the message, "DFHSM is recalling dataset xyz for user jkl" as it pulled all of your storage back online was a pain, and we all thought it would be neat to get rid of, as we migrated to workstations. But in retrospect, HSM was great, never having to worry about your data quantity. That's compared with having to root through $HOME every few months to take care of quota problems.
The living have better things to do than to continue hating the dead.
Hewlett-Packard Company developed a product that did this automagically. It was an external RAID system that connected via one or two SCSI busses to a host. All incoming data was stored in RAID 0/1; striped and mirrored. (aka RAID 6 and RAID 10). As the storage filled up, unused data was automagically migrated to more space-efficient RAID 5. Data that had been accessed recently remained in RAID 0/1. You could add disk drives and it would automagically include the drives (but you would have to use LVM or other utilities in the OS to increase its file system.) You could mix two drive sizes, say, 18GB and 36GB, without trouble. If a drive failed, the array would rebuild reduncancy. If another drive failed, ditto. It was fast, it was fully redundant.
But it was a lot smarter than the admins who had to use it so it wasn't very popular.
Best regards.