maxSurge property
The maximum number of instances that can be created above the specified targetSize during the update process.
This value can be either a fixed number or, if the group has 10 or more instances, a percentage. If you set a percentage, the number of instances is rounded if necessary. The default value for maxSurge is a fixed value equal to the number of zones in which the managed instance group operates. At least one of either maxSurge or maxUnavailable must be greater than 0. Learn more about maxSurge.
Implementation
FixedOrPercent? maxSurge;