From 91ca22f3a383c72da735c54ad5c22fb82aa318ea Mon Sep 17 00:00:00 2001 From: phk Date: Wed, 20 Mar 2002 07:16:15 +0000 Subject: Swing the axe and remove some archaic features from newfs which modern diskdrives do neither need nor want: -O create a 4.3BSD format filesystem -d rotational delay between contiguous blocks -k sector 0 skew, per track -l hardware sector interleave -n number of distinguished rotational positions -p spare sectors per track -r revolutions/minute -t tracks/cylinder -x spare sectors per cylinder No change in the produced filesystem image unless one or more of these options were used. Approved by: mckusick --- sbin/newfs/newfs.8 | 85 ++---------------------------------------------------- 1 file changed, 3 insertions(+), 82 deletions(-) (limited to 'sbin/newfs/newfs.8') diff --git a/sbin/newfs/newfs.8 b/sbin/newfs/newfs.8 index aefc95d..dfcb9a1 100644 --- a/sbin/newfs/newfs.8 +++ b/sbin/newfs/newfs.8 @@ -46,24 +46,16 @@ .Op Fl a Ar maxcontig .Op Fl b Ar block-size .Op Fl c Ar cylinders -.Op Fl d Ar rotdelay .Op Fl e Ar maxbpg .Op Fl f Ar frag-size .Op Fl g Ar avgfilesize .Op Fl h Ar avfpdir .Op Fl i Ar bytes -.Op Fl k Ar skew -.Op Fl l Ar interleave .Op Fl m Ar free space -.Op Fl n Ar rotational positions .Op Fl o Ar optimization -.Op Fl p Ar sectors -.Op Fl r Ar revolutions .Op Fl s Ar size -.Op Fl t Ar tracks .Op Fl u Ar sectors .Op Fl v -.Op Fl x Ar sectors .Ar special .Sh DESCRIPTION .Nm Newfs @@ -91,19 +83,11 @@ For backward compatibility. .It Fl N Cause the file system parameters to be printed out without really creating the file system. -.It Fl O -Create a -.Bx 4.3 -format filesystem. -This options is primarily used to build root filesystems -that can be understood by older boot ROMs. .It Fl U Enables soft updates on the new filesystem. .It Fl a Ar maxcontig Specify the maximum number of contiguous blocks that will be -laid out before forcing a rotational delay (see the -.Fl d -option). +laid out before forcing a rotational delay. The default value is 1. See .Xr tunefs 8 @@ -119,14 +103,6 @@ The number of cylinders per cylinder group in a file system. The default is to compute the maximum allowed by the other parameters. This value is dependent on a number of other parameters, in particular the block size and the number of bytes per inode. -.It Fl d Ar rotdelay -This parameter once specified the minimum time in milliseconds required to -initiate another disk transfer on the same cylinder. It was used in determining -the rotationally optimal layout for disk blocks within a file. Modern disks -with read/write-behind achieve higher performance with this feature disabled, so -this value should be left at the default value of 0 milliseconds. See -.Xr tunefs 8 -for more details on how to set this option. .It Fl e Ar maxbpg Indicate the maximum number of blocks any single file can allocate out of a cylinder group before it is forced to begin @@ -167,15 +143,6 @@ currently 8%. See .Xr tunefs 8 for more details on how to set this option. -.It Fl n Ar number of distinguished rotational positions -UFS has the ability to keep track of the availability of blocks at different -rotational positions, so that it could lay out the data to be picked up with -minimum rotational latency. This parameter specifies the default number of -rotational positions to distinguish. -.Pp -Nowadays this value should be set to 1 (which essentially disables the -rotational position table) because modern drives with read-ahead and -write-behind do better without the rotational position table. .It Fl o Ar optimization\ preference .Pq Ar space No or Ar time . The file system can either be instructed to try to minimize the time spent @@ -218,57 +185,11 @@ to find the alternate superblocks if the standard superblock is lost. .Bl -tag -width indent .It Fl S Ar sector-size The size of a sector in bytes (almost never anything but 512). -.It Fl k Ar sector \&0 skew , per track -Used to describe perturbations in the media format to compensate for -a slow controller. -Track skew is the offset of sector 0 on track N relative to sector 0 -on track N-1 on the same cylinder. -This option is of historical importance only; modern controllers are always fast -enough to handle operations back-to-back. -.It Fl l Ar hardware sector interleave -Used to describe perturbations in the media format to compensate for -a slow controller. -Interleave is physical sector interleave on each track, -specified as the denominator of the ratio: -.Dl sectors read/sectors passed over -Thus an interleave of 1/1 implies contiguous layout, while 1/2 implies -logical sector 0 is separated by one sector from logical sector 1. -This option is of historical importance only; the physical sector layout of -modern disks is not visible from outside. -.It Fl p Ar spare sectors per track -Spare sectors (bad sector replacements) are physical sectors that occupy -space at the end of each track. -They are not counted as part of the sectors/track -.Pq Fl u -since they are not available to the file system for data allocation. -This option is of historical importance only. Modern disks perform their own -bad sector allocation. -.It Fl r Ar revolutions/minute -The speed of the disk in revolutions per minute. This value is no longer of -interest, since all the parameters which depend on it are usually disabled. -.It Fl t Ar #tracks/cylinder -The number of tracks/cylinder available for data allocation by the file -system. -The default is 1. -If zero is specified, the value from the disklabel will be used. -.It Fl u Ar sectors/track -The number of sectors per track available for data allocation by the file +.It Fl u Ar sectors/cylinders +The number of sectors per cylinder available for data allocation by the file system. The default is 4096. If zero is specified, the value from the disklabel will be used. -This does not include sectors reserved at the end of each track for bad -block replacement (see the -.Fl p -option). -.It Fl x Ar spare sectors per cylinder -Spare sectors (bad sector replacements) are physical sectors that occupy -space at the end of the last track in the cylinder. -They are deducted from the sectors/track -.Pq Fl u -of the last track of each cylinder since they are not available to the file -system for data allocation. -This option is of historical importance only. Modern disks perform their own -bad sector allocation. .El .Sh EXAMPLES .Dl newfs /dev/ad3s1a -- cgit v1.1