With a small but very impactful improvement, Nerdio Manager for Enterprise (NME) recently addressed a well‑known pain point around auto-scale, storage tiers, and Start VM on Connect.
The option “Set all hosts to running OS disk type” is now always visible in Auto-scale Profiles—regardless of whether hosts are actually pre-staged or not.
While this may look like a minor UI change at first glance, it has a noticeable impact on performance consistency, cost optimization, and overall user experience.
Quick refresher: Pre-stage Hosts in Nerdio
With Pre-stage Auto-scale Schedules, you can define:
- when
- how many
- session hosts
should be started or prepared in advance—typically to absorb login storms or to guarantee performance at specific times.
This feature is commonly used in scenarios where:
- host pools are highly cost-optimized
- Minimum Active Hosts = 0
- or where workloads are only required during specific time windows
The well-known Start VM on Connect challenge
This behavior mainly affects non-production or cost-optimized pooled host pools.
For personal host pools, OS disk behavior has been configurable and predictable for quite some time, as:
- the start behavior is more deterministic
- and auto-scale disk tier changes are applied reliably
However, pooled session hosts behave differently—especially when:
- Start VM on Connect is enabled
- Minimum Active Hosts = 0 is used
- and VMs are started directly by Azure, not by Nerdio
In these cases, Nerdio was previously unable to guarantee that a VM would start with the configured Running OS Disk SKU.
In practice, this meant:
- the VM could start with a lower-cost, lower-performance disk tier
- even though Premium SSD (or similar) was defined for the running state
For sporadically used pools, this often resulted in unexpected performance degradation during the first user login.
What’s new: Set the correct OS disk type in advance—without starting VMs
This is exactly the gap the new behavior closes.
With the now permanently visible option
“Set all hosts to running OS disk type”, Nerdio can:
- update stopped session hosts
- to the configured running OS disk type
- without actually powering them on
This is especially valuable for:
- pooled host pools
- Minimum Active Hosts = 0
- Start VM on Connect enabled
Even if you do not want to pre-start any VMs, you can still ensure that disk performance is already aligned with the running configuration before the first user connects.
Why this matters in real-world environments
This enhancement provides several tangible benefits:
✅ Consistent disk performance
The first user immediately gets the expected I/O performance.
✅ Better control in cost-optimized pools
Low-cost disks while idle, high performance exactly when required.
✅ No surprises in rarely used host pools
Ideal for test, training, or on-demand environments.
✅ A clean complement to Start VM on Connect
No workarounds required to ensure disk performance.
A typical use case
A very common scenario:
- An AVD pooled host pool with infrequent user activity
- Start VM on Connect enabled
- VMs stopped most of the time
- High disk performance required immediately at login
With this option, you can:
- keep storage costs low while hosts are stopped
- and still avoid performance issues when users connect
Final thoughts
This change is a great example of how Nerdio continues to refine existing features based on real operational challenges.
Especially in cost-optimized AVD designs using Start VM on Connect, this option closes an important gap between cost efficiency and user experience.
Small change in the UI—big impact in day-to-day operations.