Re: [linux-lvm] How well tested is the snapshot feature?

[Joe Thornber <joe fib011235813 fsnet co uk>]

On Sat, Jun 08, 2002 at 09:59:31AM +0100, Joe Thornber wrote:
> exceptions LVM1 and EVMS will perform the following steps:
> 
> 1) Issue read of original chunk
> 2) wait
> 3) issue write
> 4) wait

I forgot about the metadata update:

6) issue metadata write
7) wait

device-mapper batches the metadata updates, under load this amortises
the cost away (well, to a point where I can't measure it).

- Joe