chfsets - Changes attributes of AdvFS filesets
/sbin/chfsets [-F limit] [-f limit] [-B limit] [-b limit] [-o arg[,arg]]
Specifies the block usage soft limit (quota) in 1 kilobyte blocks of
Specifies the block usage hard limit (quota) in 1 kilobyte blocks of
Specifies the file usage soft limit (quota) of the fileset.
Specifies the file usage hard limit (quota) of the fileset.
-o arg [,arg]
Specifies fileset options; valid arguments are:
frag -- Uses a frag file for files or file fragments less than 8 kilo-
nofrag -- Disables the frag file for files or file fragments less than
objectsafety -- Enables object safety in the fileset to prevent object
noobjectsafety -- Disables object safety in the fileset (default).
dmapi -- Enables a fileset for data management API (DMAPI).
nodmapi -- Disables a fileset for DMAPI (default).
Specifies the name of an existing AdvFS domain.
Specifies the name of one or more filesets.
The chfsets command enables you to change and display fileset quotas (file
usage limits and block usage limits) of any AdvFS fileset. It also allows
you to turn object safety, fragging, and DMAPI on and off for the fileset.
The chfsets command without options executes the showfsets command without
options. Please refer to the showfsets manpage for an explanation of out-
Filesets can have both soft and hard disk storage and file limits. When a
hard limit is reached, no more disk space allocations or file creations
that would exceed the limit are allowed. The soft limit may be exceeded
for a period of time by setting a grace period with the edquota command.
The page size in AdvFS is 8 kilobytes. For small files that are not an even
multiple of 8 kilobytes in length, the last partial page of data is stored
in the fragment file. The use of the fragment file results in significant
disk space savings for filesets with many small files. The trade-off for
this efficient use of disk space is in degraded filesystem performance for
these small files. Disabling the fragment file trades excellent space effi-
ciency for improved filesystem performance.
The -o option with the frag argument causes files to be fragged in the nor-
mal manner. The nofrag argument causes files that normally would be fragged
not to be. Existing files are not directly affected; files with frags
retain the frags. Subsequent operations on these files will cause the files
to use the option set. If the frag file is disabled, small files will
occupy more disk space.
The -o option with the objectsafety argument ensures that the pages on disk
belonging to the fileset will be zero-filled and forced to disk before they
are available to the files. The noobjectsafety argument does not require
that the zero-filled pages be forced to disk. If you have not enabled
object safety, and if the system crashes while the file is being written,
it may be possible to access the old data.
The -o option with the dmapi argument enables a fileset for the data
management API. The nodmapi argument disables a fileset for DMAPI. If a DM
application has already made on-disk changes to the given fileset, -o nod-
mapi may not be allowed by chfsets. For more information on DMAPI, see
You must be the root user to run the chfsets command.
Only the root user can exceed fileset quotas.
If a file has frags, persistent atomic-write data logging is not allowed.
For more information, see the chfile manpage and AdvFS Administration.
The /, /usr, and /var filesets cannot be enabled for DMAPI.
Filesets that are named root, usr, or var cannot be enabled for DMAPI.
If a fileset is DMAPI-enabled, it must be the only fileset in the domain.
This is to allow a DMAPI application to more effectively manage primary
To use the DMAPI argument, the system must have the AdvFS Utilities
The following example changes the file hard limit from 11 to 200 and block
hard limit from 121 to 1000 for the credit_fs fileset in the account_dmn
domain without displaying any output:
# chfsets -b 1000 -f 200 account_dmn credit_fs
The following example turns fragging on for the credit_fs fileset in the
account_dmn domain and displays its attributes:
# chfsets -o frag account_dmn credit_fs
# chfsets account_dmn credit_fs
Id : 3a3a6f24.000d15f4.3.8002
Files : 3,SLim= 0, HLim= 0
Blocks (512) : 48,SLim= 0, HLim= 0
Quota Status : user=off group=off
Object Safety : off
Fragging : on
DMAPI : off
The utility returns a 0 (zero) on success and a 1 (one) on failure.
Commands: chfile(8), df(1), edquota(8), quotaon(8), quotaoff(8),