Peak Load · /// Spike Validation
Model the peak before the calendar lands on it.
Finance-close, year-end, open-enrolment, e-commerce peak — predictable calendar events that production discovers too late. LoadGen spike simulation models the peak with measured concurrency across Citrix HDX, AVD ARM, Horizon, RDS, Web. Measured peak vs modelled peak — close the gap before users do.
Spike + soak + warm-up + cool-downCross-vendor (Citrix · AVD · Horizon · RDS · Web)Measured peak, not estimated
Spike simulation — measured peak vs modelled peak.
The Problem
Calendar peaks beat steady-state assumptions.
Most VDI estates are sized for steady-state load. The peak event — finance-close Monday morning, year-end open-enrolment, Black-Friday e-commerce surge — exposes the gap. Production discovers it; spreadsheet sizing didn’t.
Steady-state hides the peak.
Capacity dashboards report steady-state averages. Peaks live in the percentiles — p95 logon-time, p99 broker queue depth — that only appear under deliberate spike load.
Spreadsheet models miss the cliff.
Linear capacity models assume gradual scaling. Real peaks are non-linear — host pools, brokers, and FSLogix shares break at threshold counts not visible in linear extrapolation.
Multi-stack peaks need cross-vendor framing.
A finance-close peak crosses Citrix (legacy), AVD (newer apps), and Web (portal). One peak event, three test plans — unless the scenario engine spans all three.
Why LoadGen for peak validation
One scenario shape. Spike phases. Cross-vendor.
The same scenario engine that runs steady-state load tests adds deliberate spike phases — warm-up, steady, spike, cool-down. Cross-vendor: Citrix HDX, AVD ARM, Horizon, RDS, Web. Measured peak surfaces before the calendar event.
Spike phase profiles
Configurable warm-up / steady / spike / cool-down phases. Spike-shape profiles model the actual peak event — finance-close burst, open-enrolment ramp, Black-Friday surge.
Per-step latency at peak
Per-step latency, p95 / p99, broker queue depth, host-pool density — visible as the spike progresses. The component that breaks first surfaces before production does.
Cross-vendor on one timeline
Citrix HDX peak, AVD ARM peak, Web portal peak — captured on the same scenario engine, overlaid on one chart for direct comparison.
Spike orchestration
Warm-up → steady → spike → cool-down, live.
The cockpit during a spike run. vUsers ramping into the peak, per-step latency growing, broker queue depth surfacing. The gap between modelled peak and measured peak closes in front of you.
- vUsers ramp across warm-up / steady / spike / cool-down — visible as the run progresses.
- Per-step latency + p95 / p99 + broker queue depth at peak.
- Modelled peak vs measured peak gap closes in front of you.
- Spike data feeds straight into capacity sign-off for the calendar event.
Live orchestration cockpit during a spike run.
Capability
What ships with peak-load validation.
Configurable spike profiles
Warm-up / steady / spike / cool-down phases authored in the load-profile wizard. Spike shape, duration, and concurrency tuned per scenario.
Learn moreLive cockpit at peak
Per-step latency, p95 / p99, broker queue depth visible as the spike progresses. Multi-region concurrency for honest geo-distributed peak modelling.
Learn moreSUT Monitoring during spikes
Citrix Broker, AVD connection-broker, Horizon Connection Server, RDS Connection Broker counters bound to every spike test. Infra correlation at peak.
Learn moreMulti-test comparison
Up to 5 spike runs overlaid — week-over-week regression, modelled vs measured, pilot vs production scale.
Learn moreCross-vendor scenario reuse
The same .lgs scenario authored once spikes across Citrix, AVD, Horizon, RDS, Web. One peak event, one scenario.
Learn moreEvidence for capacity sign-off
Every spike run captured in queryable history. Exportable to PDF / JSON for the peak-event readiness review.
Learn moreCross-vendor overlay
Citrix peak vs AVD peak vs Web peak — on one chart.
Multi-test overlay compares spike runs across stacks. Same scenario shape, three stacks, one chart — the cross-vendor peak picture in one view.
- Same .lgs scenario spikes across Citrix HDX, AVD ARM, Web — up to 5 runs overlaid.
- Drill into Moments, Errors, per-step deltas at peak.
- Identify which stack breaks first under the modelled peak.
- Cross-vendor peak readiness in one chart, not three spreadsheets.
Multi-test overlay — cross-vendor spike comparison.
Outcomes
What peak validation looks like in numbers.
Before
Spreadsheet
After
Measured
Before
Multi-tool
After
One chart
Before
8
After
1
Before
Weeks
After
Days
Where peak validation lives
Three calendar events worth measuring.
Finance-close Monday morning
Monday-morning logon storm + finance-app load. Spike profile models the simultaneous arrival of every controller / accountant / ops user — capacity sized for the burst, not the average.
See use caseYear-end / open-enrolment
Predictable calendar events with disproportionate load. Multi-week spike validation models the ramp-up across the event window — measured before users hit the calendar.
See use caseE-commerce / Black-Friday
Web portal spike testing alongside Citrix back-office and AVD operations staff. Cross-vendor peak readiness on one scenario engine.
See use caseValidate your peak before it happens.
We’ll author a spike scenario in the wizard on a call, fire it from Full or VDI agents, and show you measured peak across Citrix / AVD / Horizon / RDS / Web — live, before the calendar event.
Questions
Frequently asked.
How does peak validation differ from steady-state load testing?
Steady-state load tests model a constant level of concurrent users. Peak validation deliberately spikes the load — warm-up / steady / spike / cool-down — to surface non-linear breakpoints (broker queue saturation, FSLogix share contention) that steady-state misses.
Can the spike profile model real calendar events?
Yes. The load-profile wizard configures phase shape, duration, and concurrency. Customer scenarios commonly include Monday-morning finance-close (sharp 30-minute spike), year-end (multi-day ramp), and e-commerce flash sales (5-minute peak).
Does this work for multi-stack peaks (Citrix + AVD + Web)?
Yes — the same .lgs scenario engine drives Citrix HDX, AVD ARM, Horizon, RDS, and Web. One peak event, one scenario authored in the wizard, replayed across all stacks. The multi-test overlay shows the cross-vendor peak picture on one chart.
How accurate is the modelled peak vs the real peak?
Published target for host-pool right-sizing is ±5% accuracy on AVD, compared against ±40% typical of spreadsheet sizing models (source: /platforms/avd OUTCOMES). Numbers come from per-host measured concurrency, not modelled assumptions.
What does peak validation cost?
Load Testing module is €1,099 per week at the 50-vUser tier, scaling to 25,000 vUsers. Multi-week terms run from 1 week to 5 years. Peak-event engagements often combine Load Testing with End-to-End Monitoring (€899/Agent/mo) for SLA tracking through the event window.
Can LoadGen Services manage the peak validation for us?
Yes. LoadGen Services (consulting + managed runs) is available where in-house bandwidth is tight — particularly common for high-stakes calendar events (year-end close, regulatory reporting peak).
