Reservations

Important

This feature is available only to organizations that belong to the IBM Q Network.

Overview

Under standard operating conditions, IBM Quantum systems accept jobs according to the dynamic priority assigned by the fair-share queuing system.

Normal device queuing operation.

While this system attempts to balance workloads for the benefit of all users, there are often use cases where you may require limited-time access at a higher priority level. IBM Quantum Experience provides two means by which users associated with a selected provider can gain elevated access to specific systems over a specified period of time: Priority mode and Dedicated mode. Depending on your hub configuration, if you are a hub admin or group admin, you can reserve time in advance on a particular system with the Systems Reservations tool.

System reservations and fair-share allocation

System time accumulated while using system reservations does not count towards a provider’s fair-share allocation amount.

Priority mode

When submitting many self-contained jobs or hosting events (i.e., courses, tutorials, or hackathons), you may need to by-pass the queue altogether and send jobs from a given provider straight to the front of the queue for one or more systems. This is called priority mode access in IBM Quantum Experience.

Priority queueing.

Priority queuing for provider #3.

In priority mode, all jobs from the specified provider submitted during the scheduled priority mode time go to the front of the queue for the specified system. Jobs process in the order in which the provider receives them (first-in first-out). Jobs submitted before a priority mode reservation are considered part of the normal queue, and do not move to the front. If the provider with priority access does not submit jobs, then the normal fair-share queue pipeline opens until another priority job is received.

Priority queuing with no priority jobs.

Normal queue operation continues until a new job from provider #3.

In priority mode, the system is never idle as long as the providers are submitting jobs. At the end of a priority mode reservation, any priority jobs that have not be executed will return to the standard fair-share queue.

Dedicated mode

If you need sole access to a specific quantum system for a given provider, select dedicated mode when making a reservation.

Dedicated mode with dedicated jobs.

Provider #2 in dedicated mode.

Unlike priority mode, the standard fair-share queue is always blocked when the device is in dedicated mode.

Dedicated mode with no dedicated jobs leaves the device idle.

Dedicated mode with no dedicated jobs from provider #2 leaves the device idle.

This therefore allows users to implement algorithms where input circuits are conditioned on previous results, e.g., iterative and near-time compute methods, without having to wait for other users’ results to process. If the dedicated provider has multiple users, then a single user’s jobs may be queued behind those of other users in the provider, as the execution is first-in first-out. Other functionality is identical to that of priority mode.

Selecting the correct reservation mode

To determine the appropriate mode for your reservation, consider the table below, which offers guidance based on some common use cases.

Common Reservation System Use Cases

Use case

Reservation mode

In-class demonstrations

Priority mode / Dedicated mode

Hackathon or tutorial sessions

Priority mode

Executing many independent circuits

Priority mode

Iterative and near-time compute algorithms

Dedicated mode

Jobs involving detailed noise analysis

Dedicated mode

Time-critical projects

Dedicated mode

Make a new reservation

Select the Your reservations calendar icon in the left navigation bar.

The remaining amount of reservable time allotted to your hub displays at the bottom of the page as Monthly credit remaining.

  1. Select a system. Select a backend and provider (group/project) to reserve. You will only see the systems that are available for future scheduling.

  2. Choose a date. Choose an available date and time by selecting a date on the calendar. Only available dates will be clickable.

  3. Reserve a time slot. Enter a start and end time of your reservation in 24-hour format. The maximum length per reservation is listed below the time slot table.

  4. Click on Make reservation. The Make reservation button is only clickable if the reservation time slot you entered is valid.

Important

Reservations should be scheduled at least two hours ahead of time to prevent jobs currently on the device from overflowing into the allotted time.

View your reservations

Select the Your reservations tab to view your upcoming reservations.

Cancel a reservation

  1. Select the Your reservations tab to view your upcoming reservations.

  2. Click the checkbox to the left of the reservation to cancel.

  3. Click the Cancel Reservations button that appears above the list of reservations.

Warning

You cannot cancel a time slot once it has begun, and the full length of the time slot will be deducted from your provider.