On 02/23/2011 09:37 AM, Avi Kivity wrote:
On 02/23/2011 05:31 PM, Anthony Liguori wrote:
what about snapshots? Are we okay having a feature in a prominent
format that isn't going to meet user's expectations?
Is there any hope that an image with 1000, 1000, or 10000 snapshots
is going to have even reasonable performance in qcow2?
Are thousands of snapshots for a single image a reasonable user
expectation? What's the use case?
Checkpointing. It was the original use-case that led to qcow2 being
invented.
I still don't see. What would you do with thousands of checkpoints?
Er, hit send to quickly.
HPC is a big space where checkpointing is actually useful. An HPC
workload may take weeks to run to completion. If something fails during
the run, it's a huge waste of time. However, if you do regularl
checkpointing, a failure may only lose a few minutes of work instead of
the entire weeks worth of work.
Regards,
Anthony Liguori
