Support for shingled magnetic recording devices

Posted Mar 28, 2014 17:52 UTC (Fri) by Creideiki (subscriber, #38747)
In reply to: Support for shingled magnetic recording devices by giraffedata
Parent article: Support for shingled magnetic recording devices

Wouldn't that application be "every log-structured file system ever"? New data and metadata is written to the end of the log, and GC-copied to another zone as necessary. Keep a pointer to the currently valid root block in the random-write zone.

Support for shingled magnetic recording devices

Posted Mar 28, 2014 23:27 UTC (Fri) by giraffedata (guest, #1954) [Link] (1 responses)

I don't know what "GC-copied to another zone" is, but ordinary log structured filesystems are ideal applications for shingled disks. An application that works with a log structured filesystem on a traditional disk drive today could presumably use shingled disk instead for a 20% cost saving. Not counting any costs associated with having special disk drives provisioned for that application.

Support for shingled magnetic recording devices

Posted Mar 29, 2014 7:05 UTC (Sat) by Creideiki (subscriber, #38747) [Link]

That's probably my LISP bias showing, assuming everyone is intimately familiar with garbage collection strategies. A copying garbage collector partitions storage into two zones, using only one at a time, and when that one gets full copies only the live data to the other one, leaving the garbage behind to get overwritten in the next cycle.