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VDI · /// Capacity Planning

Stop guessing how many sessions your VDI estate can hold.

Measured concurrency, not spreadsheets. The same scenario engine runs on Citrix (7-step wizard, Basic ICA + Enhanced HDX), AVD (7-step wizard, Classic/ARM toggle), Horizon (generic wizard, load-test Horizon at concurrency via L&P), and RDS (8-step shared RDP/RDS wizard). Generic p95 captured on every stack.

Citrix · AVD · Horizon · RDSSame engine, every targetMeasured concurrency, not guesses

Live orchestration cockpit. Measured concurrency across stacks.

The Problem

Spreadsheet sizing breaks first on production weekends.

Vendor-supplied calculators and spreadsheet sizing models give round numbers that look defensible until a production peak proves them wrong. Without measured concurrency on the actual session host, capacity claims live on slides, not in production.

Pilot pools that lie.

A small pilot proves nothing about a production cohort. Without measured concurrency on the actual session host (Citrix, AVD, Horizon, or RDS), capacity claims live on slides, not in production.

Infrastructure invoices don’t care.

Wrong session-host SKU, wrong host-pool count, wrong storage sizing. The monthly invoice tells the truth. Spreadsheet sizing models miss the components that actually break first under measured load.

Multi-stack reality.

Most enterprises run more than one VDI stack: Citrix in one division, AVD in another, Horizon in a third, RDS for legacy apps. Capacity planning needs to compare them on the same scenario shape, not three different spreadsheets.

Why LoadGen for capacity planning

One scenario engine. Four VDI stacks. Measured.

Author a scenario once. Replay it on Citrix, AVD, Horizon, and RDS. Capture real session-host pressure on each. The same `.lgs` workload produces real numbers across stacks for direct comparison.

Measured concurrency, not modelled

Full and VDI agents run as actual Citrix, AVD, Horizon, or RDS sessions. Activate, Reset, and Kill operations land per-session on real session hosts. No thread-based abstractions.

Same scenario, four stacks

The same `.lgs` workload replays unmodified across all four target stacks. Generic p95 captured per transaction on each, on the same scenario shape.

SUT Monitoring on every host

Bind generic Windows performance counters to every test via the SUT Monitoring step. Capacity correlates with infrastructure health on one timeline.

Cross-stack validation

The same scenario shape, on every VDI stack.

Author once. Run on Citrix, AVD, Horizon, and RDS. Compare generic p95 on each stack on one chart. Measured, not modelled.

  • Same `.lgs` scenario runs unmodified on Citrix, AVD, Horizon, and RDS.
  • Up to 5 runs overlaid on one chart for direct comparison.
  • Generic p95 captured per transaction on every stack.
  • Numbers feed straight into capacity sign-off: session-host SKU, storage sizing, host-pool count.

Multi-test overlay. Citrix vs AVD on the same scenario.

Peak validation

Spike testing for finance-close, year-end, and open enrolment.

The same scenario at growing scale shows where the host pool breaks first. Phase-by-phase validation between cohorts. Cutover signs on data, not opinion.

  • Warm-up, steady, spike, and cool-down phases. Visible as the run progresses.
  • Per-step latency, generic p95, and error hotspots during the run.
  • Compare modelled peak against measured peak. Close the gap before production users do.
  • Wire into release flow to block deploys on regression.

Spike simulation. Measured peak vs modelled peak.

Proof

Numbers from the platform.

1.45M+

Tests run

across the customer base

6

Platforms covered

Citrix · AVD · Horizon · RDS · Web · FAT

From €1,099

Per week · transparent

starts at 50 vUsers

50 → 25,000+

vUsers · license tiers

starts at 50, scales up to 25,000+

Right-size your VDI estate with measured data.

We’ll author a scenario in the wizard on a call, fire it from Full or VDI agents against your Citrix, AVD, Horizon, or RDS pool, and show you measured concurrency. Not spreadsheet numbers.

Questions

Frequently asked.

Does LoadGen do capacity planning for Citrix, AVD, Horizon, AND RDS?

Yes. The same scenario engine drives all four. Author once, replay on each stack. Per-stack wizards: 7-step Citrix (Basic ICA + Enhanced HDX), 7-step AVD (Tenant · Client · Resource · Classic/ARM), generic wizard for Horizon, and 8-step shared RDP/RDS wizard. Generic p95 captured on every stack.

What measurement does LoadGen capture on each stack?

Generic p95 is tracked for every transaction on every stack. Per-step latency and host-pool density visible as the run progresses on the live cockpit. SUT Monitoring binds generic Windows performance counters to each execution.

Can we compare Citrix capacity against AVD capacity in one engagement?

Yes. The same `.lgs` scenario runs unmodified on both stacks. The cockpit overlays generic p95 on each side for direct comparison on the same scenario shape. See /use-cases/citrix-to-avd-migration.

How is Horizon capacity tested without a dedicated Horizon wizard?

Horizon runs through the generic wizard on the same scenario engine. LoadGen can load-test Horizon at concurrency through the same scenario engine via Load & Performance Testing. There is no separate Horizon wizard and no native vCenter integration.

How does this work for peak-event capacity (finance-close, year-end)?

Spike-simulation phases (warm-up, steady, spike, cool-down) model the peak deliberately. Per-step latency and host-pool density visible as the run progresses. Measured peak vs modelled peak gap closes before production users hit the calendar.

What does VDI capacity planning cost?

Load Testing is €1,099 per week at the 50-vUser tier. License tiers run from 50 to 25,000 vUsers; 25,000+ users have been tested by LoadGen, and LoadGen scales with available test infrastructure and agent capacity. Terms run from 1 week to 5 years. Capacity-planning engagements typically combine Load Testing with End-to-End Monitoring (€899 / Agent / month) for Service Levels tracking after sign-off.

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