.TH LFS-HEAT 1 2024-08-30 Lustre "Lustre User Utilities"
.SH NAME
lfs-heat_get, lfs-heat_set \- commands used to interact with file heat features
.SH SYNOPSIS
.SY "lfs heat_get"
.IR FILE ...
.SY "lfs heat_set"
.RB [ --help | -h ]
.RB [ --clear | -c ]
.RB [ --on | -O ]
.RB [ --off | -o ]
.IR FILE ...
.YS
.SH DESCRIPTION
These are a set of lfs commands used to interact with Lustre file heat feature.
Currently file heat is only stored in memory with file inode, it might be reset
to be zero at any time with the release of the inode due to memory reclaim.
.B lfs heat_get
gets the file heat on the file list.
.B lfs heat_set
sets the provided file with heat flags on the file list.
.SH OPTIONS
.TP
.BR -c ", " --clear
Clear file heat on given files.
.TP
.BR -h ", " --help
Print usage message.
.TP
.BR -o ", " --off
Turn off file heat on given files.
.TP
.BR -O ", " --on
Turn on file heat on given files.
.SH EXAMPLES
Turn on file heat support for the Lustre filesystem:
.RS
.EX
.B # lctl set_param llite.$FSNAME*.file_heat=1
.EE
.RE
.PP
Turn off file heat support for the Lustre filesystem:
.RS
.EX
.B # lctl set_param llite.$FSNAME*.file_heat=0
.EE
.RE
.PP
Display current file heat for foo:
.RS
.EX
.B # lfs heat_get /mnt/lustre/foo
flags: 0
\&
readsample: 0
writesample: 16
readbyte: 0
writebyte: 16777216
.EE
.RE
.PP
Clear the file heat for foo:
.RS
.EX
.B # lfs heat_set -c /mnt/lustre/foo
.EE
.RE
.PP
Turn off file heat for foo:
.RS
.EX
.B # lfs heat_set -o /mnt/lustre/foo
.EE
.RE
.PP
Turn on file heat for foo:
.RS
.EX
.B # lfs heat_set -O /mnt/lustre/foo
.EE
.RE
.SH AVAILABILITY
The
.B lfs heat_get
and
.B lfs heat_set
commands are part of the
.BR lustre (7)
filesystem package since release 2.13.0
.\" Added in commit v2_12_52-52-gae723cf816
.SH SEE ALSO
.BR lfs (1),
.BR lustre (7)