chfsets - Changes attributes of AdvFS filesets
/sbin/chfsets [-F limit] [-f limit] [-B limit] [-b limit]
[-o arg[,arg]] domain [fileset...]
Specifies the block usage soft limit (quota) in 1 kilobyte
blocks of the fileset. Specifies the block usage hard
limit (quota) in 1 kilobyte blocks of the fileset. Specifies
the file usage soft limit (quota) of the fileset.
Specifies the file usage hard limit (quota) of the fileset.
Specifies fileset options; valid arguments are:
frag -- Uses a frag file for files or file fragments
less than 8 kilobytes (default).
nofrag -- Disables the frag file for files or file
fragments less than 8 kilobytes.
objectsafety -- Enables object safety in the fileset
to prevent object reuse.
noobjectsafety -- Disables object safety in the
dmapi -- Enables a fileset for data management API
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 output.
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
efficiency for improved filesystem performance.
The -o option with the frag argument causes files to be
fragged in the normal 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 zerofilled
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
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 nodmapi 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
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 storage.
To use the DMAPI argument, the system must have the AdvFS
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
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
Commands: chfile(8), df(1), edquota(8), quotaon(8), quotaoff(8), showfdmn(8), showfsets(8)
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