[Gluster-users] Concurrency limitation?

[Brian Candler]

On Tue, Feb 07, 2012 at 04:17:19PM +0100, Arnold Krille wrote:
> I did some similar test but with a slower machine and slower disk.
> The "problem" with distributed filesystems is the distributed locking.

I'm not using a block-level distributed filesystem like GFS or OCFS.

GlusterFS is a file-level protocol, more like NFS, and as far as I know
there is no inherent locking between clients.

> And when the volume stretches across several machines, 
> even though the reading might be done from the local disk, the locking has to 
> be synchronized across all brick-machines. Another limit.

Which locking is that? Can you point me to any documentation which says so,
or the part of the source code which implements it?  Why, when I simply read
a file, would a lock need to be created anywhere?

Regards,

Brian.