NAME

lfschkpt − Display or modify the checkpoint fields of an LFS file system. 

SYNOPSIS

lfschkpt [options] deviceName

OPTIONS

deviceNameThe device on which the file system should be created. The partition should contain an unmounted LFS file system. WARNING: This program should not be run on a running (attached) file system. 

−maxNumCacheBlocks NumCacheBlocks
NumCacheBlocks is the maximum number of file cache blocks to used during cleaning. 

−checkpointInterval CheckpointInterval
CheckpointInterval is the frequency in seconds to perform checkpoints. 

−domainNumber DomainNumber
DomainNumber is the Sprite domain number assigned to this file system.  A value of -1 will caused to system to assign it a number upon the next attach. 

−serverID idid is the Sprite hostname id specified in the superblock.  This id is used to inform a machine of its name at boot time. 

−maxUtilization Utilization
Utilization is the maximum fraction of the disk space usable by the file system. 

−maxDesc NumDesc
NumDesc is the maximum number of descriptors available in the file system. A negative value causes mklfs to compute this number based on the disk size. 

−segAlignment Alignment
Alignment is the alignment in bytes where the first segment should start. 

−minNumClean numSegments
numSegments is minimum number of clean segments to maintain in the file system. This number acts as an lower bound as when to start segment cleaning. 

−minFreeBlocks numBlocks
numBlocks is minimum number of free blocks before the system will stop allowing block allocate requests.  This number decides the maximum disk space utilization. 

−wasteBlocks numBlocks
numBlocks is the number of blocks the system will waste while filling in a segment. 

−numSegsToClean numSegments
numSegments is number of segments the segment cleaner will generate This number acts as the threshold under which cleaning is stopped. 

−bothDisplay both checkpoint regions. 

−writeApply requested changes to the disk. 
 

DESCRIPTION

Lfschkpt displays the LFS superblock and checkpoint region headers and allows for the user to specify changes to these data structures.  With no arguments specified, Blfschkpt displays the data structures.  The −write option allows changes to be made to the disk and should only be run when the file system is not attached.  The rest of the options specify field names in the LfsSuperBlock and LfsCheckPointHdr data structures that may be changed.   A field value of -2 (the default) means no change. 

WARNING

Lfschkpt does no error checks on changes being made. It is possible to render the file system unattachable with this command. 

KEYWORDS

filesystem, LFS, sprite
 

Sprite version 1.0  —  May 31, 1991