Re: FFS - Still using rotational delay with modern disks?
Greg 'groggy' Lehey <[email protected]> Tue, 18 Dec 2012 10:23:51 +1100
| Newsgroups | gmane.os.freebsd.devel.file-systems,gmane.os.freebsd.performance |
|---|---|
| Organization | The FreeBSD Project |
| Message-ID | <[email protected]> |
On Monday, 17 December 2012 at 16:44:11 -0500, Dieter BSD wrote: > The newfs man page says: > > -a maxcontig > Specify the maximum number of contiguous blocks that will be laid > out before forcing a rotational delay. The default value is 16. > See tunefs(8) for more details on how to set this option. > > Is this still a good idea with modern drives where the number of > sectors per track varies, and no one but the manufacturer knows how > many sectors a particular track has? No. It looks as if this, and also a number of comments in sys/ufs/ffs/fs.h and sys/ufs/ffs/ffs_alloc.c, are leftovers from the Olden Days. The value isn't used anywhere that I can see. Unless somebody can show that I'm wrong, I'd suggest that this is a documentation issue that I can take a look at. Greg -- Sent from my desktop computer. Finger [email protected] for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua
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