Once I stopped our instance and modified the size of one of the EBS volumes. Then, that EBS is stopping at in 'in-use - optimizing (60%)' status. I suppose it can sometimes happen to take long time for optimizing up to 24hours. But we need to start our EC2 instance as soon as possible.
I'm just wondering if it is possible to start EC2 instance, one of the EBS in optimizing status not completed yet. That EBS is not root volume, but the important volume contains database files.
Any advice would be appreciated.
Yes you can run the EC2 instance even whilst the EBS volume is optimising.
Whilst it is occuring you might find that the performance varies between both modifications however, it will never be lower than the minimal performance of either previous or new configuration.
While the volume is in the optimizing state, your volume performance is in between the source and target configuration specifications. Transitional volume performance will be no less than the source volume performance. If you are downgrading IOPS, transitional volume performance is no less than the target volume performance.
More information available in the documentation.