Office 365 Throttling

What is throttling?

Throttling is a security instrument that ensures the services remain fit and responsive. Throttling limits, the workload coming into the system. Without this, services could become unresponsive causing interruptions for everyone sharing the resources.

 

What can be throttled?

Any Office 365 workload being migrated has the potential of being throttled at some point in time during a migration project. Throttling has the potential of occurring in the source and/or target environment. The most common workloads to experience throttling are SharePoint and OneDrive. Therefore, any migration job that involves the migration of files, folders, documents, libraries and the like are more likely to be subject to throttling. These means Users, Unified Groups and Teams are all subject to more frequent throttling then mailboxes and archives.

 

Is throttling common?

Throttling is more common with the migration of SharePoint and OneDrive content. Mailbox migrations do experience throttling but it is not as common with Exchange Online. Throttling is likely any time enough sync jobs generate more than 15 GB an hour of traffic to an Office 365 tenant. Based on performance validations this is normally around 10 – 15 parallel users with OneDrive and OneNote.

 

How do I get the most throughput without being throttled?

Throttling may occur at anytime depending on many variables. Such as time of day, amount of data, resource usage by other users and applications, the list goes on and on. However, throttling is most likely to occur during the initial sync of a large users, groups and Teams.

There are many general strategies one may deploy to help avoid throttling situations.

  1. Reduce the size of the data being migrated. Have user’s clean-up as a pre-migration activity and don’t migrate what isn’t required, such as orphaned or unused accounts.
  2. Schedule Syncs outside of business hours, overnight and weekends are ideal.
  3. Limit background application activity during Syncs to reduce the chance of throttling.
  4. Manage Syncs wisely, migrate in smaller waves. In other words, don’t try to overburden the system. Use historical sync data to determine your ideal size based on the workloads you are moving.
  5. Migrate by Size. To better predict how long an event will take, assemble your users, groups and teams into waves by their size profile. This is especially helpful during cutover events when timing can be the most important element of the event.

 

How do I know when I am being throttled?

Power365 is designed to manage the load without causing excessive throttling. Keep in mind a little throttling is good. It means we are using the full capacity of system without overwhelming it.

 

What should I do if I am being throttled?

Throttling is simply caused by too much load being placed on a system at a given period.

Power365 is designed to manage the load without causing excessive throttling. Keep in mind a little throttling is good. It means we are using the full capacity of system without overwhelming it.

Always be sure to follow best practices outlined in “How do I get the most throughput without being throttled?”.

 

How does Power365 help prevent throttling?

Power365 follows Microsoft guidance around, app-based authentication, permissions settings, App IDs, combined with best practices for discovering files and detecting changes at scale.

There are different usage patterns between end user traffic and an application doing background activities such as migration. It is important to identify user traffic versus application traffic.

To provide a stable platform and more reliable service, Power365 has transitioned from user-based authentication to app-based authentication to provide greater reliability to our end users and partners.

Migration is a background task application and by transitioning to app-based authentication, Power365 benefits from the elastic capability of off-peak time to have more resources.

In addition, Power365 focuses on these areas to provide the best experience possible.

  • Managing concurrent parallel migrations through proprietary queue management.
  • Decorating http traffic with an ISV Identifier that is registered and known by Microsoft.
  • We use a retry policy that follows Microsoft best practices.
  • We utilize Application permissions when required to lessen the throttling thresholds.

 

How many concurrent syncs does Power365 allow?

Power365 has two (2) policy thresholds that help reduce the chances of too much throttling occurring against an Office 365 tenant. These thresholds are managed by Power365 and may change as required.

  1. Mailbox Concurrency: 200 Parallel Jobs
  2. OneDrive Concurrency: 16 Parallel Jobs

 

What is the average throughput?

Throughput is determined by many factors and some users, groups or teams may be slower than their counterparts based on the complexity of the data. That said, there are some averages based on workloads that may help with planning.

  1. Mailbox – 1 – 3 GB an hour per mailbox
  2. OneDrive – 15 to 20 GB an hour aggregate across all jobs

Please note, every Unified Group and Team contains a Mailbox component and a SharePoint component that the different sync job types will manage.