Re: [Gluster-devel] Question about the current design on locks

[Vikas Gorur]

On Wed, Jul 11, 2007 at 09:53:58PM -0300, Daniel van Ham Colchete wrote:
> People,
> 
> what's the current design of locks in GlusterFS? I couldn't find the answer
> looking the sources.
> 
> Being more specific: how does cluster/unify and cluter/afr handle flock()
> and fcntl byte-ranged advisory locking? Is this lock cluster-aware? I'm
> considering only normal circumstances. I'm not worried with split-brain or
> another type of rare situations.

POSIX record locking support is provided by the posix-locks translator
in GlusterFS (features/posix-locks). It supports both advisory and
mandatory locking. You'd want to load this translator on each server, so
that a lock would be visible to all clients.

Spec file example:

volume locks
  type features/posix-locks
  subvolumes brick1
# option mandatory on
end-volume

Vikas