topic reallocate vs wafl scan reallocate in ONTAP Discussions

reallocate vs wafl scan reallocate

saranraj456 — Thu, 05 Jun 2025 06:20:01 GMT

Frndz,

What was d difference between these two commands

reallocate start <vol name>

wafl scan reallocate

Re: reallocate vs wafl scan reallocate

DOUGLASSIGGINS — Thu, 30 Aug 2012 16:04:38 GMT

Greetings,

I believe this command is the same thing. As reallocate use matured the command became reallocate. The old way of doing things was through wafl scan reallocate.

These days I have been using reallocate.

reallocate vs wafl scan reallocate

saranraj456 — Fri, 31 Aug 2012 08:58:13 GMT

Actually as per the man page define WAFL scan reallocate will do the restructuring of ALL blocks even if it is assume not to give any performance improvements. If that is the case why we need to go for this option.

Saran

Re: reallocate vs wafl scan reallocate

DOUGLASSIGGINS — Fri, 31 Aug 2012 15:26:56 GMT

Greetings,

The -f parameter with reallocate command is equivalent:

In addition, full one-time reallocation of a large file, LUN or a whole volume, can be forced by using the -f option with reallocate start. A full reallocation will reallocate data unless the performance is predicated to be worse after the movement. Full reallocation is equivalent to using wafl scan reallocate.

Reallocate should only be used if you see some disks in an aggregate with much more utilization than others. The reallocate measure command takes a look and takes a best guess at whether or not the reallocation will provide benefit.