Date: Fri, 24 Jul 2015 12:34:00 +0000 From: Andrew Duane <aduane@juniper.net> To: Don whY <Don.whY@gmx.com>, "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org> Subject: RE: format/newfs larger external consumer drives Message-ID: <DM2PR05MB736A3B6ED705DE07BDB322DCE810@DM2PR05MB736.namprd05.prod.outlook.com> In-Reply-To: <55B18C45.4030707@gmx.com> References: <CAA3ZYrDcUHsYvPDzqbzVsg8LUUP6PtOPh8CQQ_E4a%2BHsmA1aoA@mail.gmail.com> <55B18C45.4030707@gmx.com>
next in thread | previous in thread | raw e-mail | index | archive | help
> -----Original Message----- > From: owner-freebsd-hackers@freebsd.org [mailto:owner-freebsd- > hackers@freebsd.org] On Behalf Of Don whY > Sent: Thursday, July 23, 2015 8:52 PM > To: freebsd-hackers@freebsd.org > Subject: Re: format/newfs larger external consumer drives >=20 > On 7/22/2015 2:08 PM, Dieter BSD wrote: > > Don whY asks: > >> So, fsck's effort (and execution *time*) is based *mostly* on inodes? > > > > I don't know about *mostly*, but reducing the number of inodes > > significantly reduced fsck time for me. >=20 > OK. I may try building a filesystem, loading a fixed set of files > (assorted) onto it, then fsck'ing it. Then, rebuild with a different > block/frag/inode configuration and try again (same file set). At the ver= y least, it > will be an interesting experiment! FSCK has 5 passes, each of which checks a different "thing" in the filesyst= em. Each pass will depend on how many of those "things" there are to check.= One checks inodes and cylinder groups, one checks all blocks, one checks a= ll directory and file entries, and so on. So fewer inodes will help, but mo= re files eat up the savings, etc. Some experiments can tell you how long it= takes to check each and what the savings would be. Also remember that each inode takes 128 bytes on disk. So a billion unused = inodes wastes a 128 GB on the disk. > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org= "
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?DM2PR05MB736A3B6ED705DE07BDB322DCE810>