The branch main has been updated by eugen: URL: https://cgit.FreeBSD.org/src/commit/?id=dbc4a1c69191909a7210cad6da46b755557d0d34
commit dbc4a1c69191909a7210cad6da46b755557d0d34 Author: Eugene Grosbein <[email protected]> AuthorDate: 2025-12-09 14:47:26 +0000 Commit: Eugene Grosbein <[email protected]> CommitDate: 2025-12-09 14:47:26 +0000 trim.8: minor update for manual page Further explain that trim(8) is not for trimming free blocks in populated file systems/ZFS pools, as people still take it wrong sometimes. MFc after: 1 week --- usr.sbin/trim/trim.8 | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/usr.sbin/trim/trim.8 b/usr.sbin/trim/trim.8 index eef369703715..7c8f3b36d520 100644 --- a/usr.sbin/trim/trim.8 +++ b/usr.sbin/trim/trim.8 @@ -23,7 +23,7 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.Dd October 1, 2025 +.Dd December 9, 2025 .Dt TRIM 8 .Os .Sh NAME @@ -51,11 +51,21 @@ utility erases specified region of the device. It is mostly relevant for a storage that implements trim (like flash based, or thinly provisioned storage). .Sy All erased data is lost. -Alternatively, refer to the +.Pp +The +.Nm +utility should not be used upon mounted file system or active devices +being a part of imported ZFS pool or other software RAID, and the kernel +does not permit such usage generally. +If used upon not mounted file system +of inactive device, the +.Nm +utility erases blocks non-selectively, whether a block is occupied or not. +Refer to the .Xr fsck_ffs 8 command having a flag .Fl E -to trim populated UFS, and to the +to trim free blocks inside populated UFS, and to the .Xr zpool-trim 8 command to trim existing ZFS pool. .Pp
