Docs: New BTRFS_IO_LIMIT option

Signed-off-by: Brendan Hide <[email protected]>

Author: zatricky

README.man

@@ -63,6 +63,10 @@ you can turn off the automatic repair (\fB\fCBTRFS\_SCRUB\_READ\_ONLY\fR)
 .IP \(bu 2
 the default IO priority is set to \fIidle\fP but scrub may take long to finish,
 you can change priority to \fInormal\fP (\fB\fCBTRFS\_SCRUB\_PRIORITY\fR)
+.IP \(bu 2
+If using systemd timers, you can also enable (`BTRFS_IO_LIMIT`) to set IO resource
+.IP \(bu 2
+limits
 
 .RE
 

README.md

@@ -46,6 +46,8 @@ __Tuning:__
 * you can turn off the automatic repair (`BTRFS_SCRUB_READ_ONLY`)
 * the default IO priority is set to *idle* but scrub may take long to finish,
   you can change priority to *normal* (`BTRFS_SCRUB_PRIORITY`)
+* If using systemd timers, you can also enable (`BTRFS_IO_LIMIT`) to set IO resource
+* limits
 
 __Related commands:__