Performance Tips

Getting the best performance out of Microsoft Identity Lifecycle Manager (ILM) is a complex subject, but the tips and tricks outlined here should make it easy to avoid the worst performance-related pitfalls.

• Never run Microsoft ILM on a virtualised platform: it's not endorsed or supported by Microsoft and for good reason. The demands made by ILM service itself and by the SQL Server service (on which it depends) make it a poor candidate for virtualisation and it will hit performance by anithing between 30% and 95%.
• Host Microsoft ILM and its Microsoft SQL Server instance on the same physical machine. Collocating these two services can improve performance by about 15%.
• Dedicate separate spindles for the SQL Server application database and its logs. Placing the database and logs on the same spindles will hit ILM performance by up to 30%. Sharing the spindles with other applications or other database instances can have an even more dramatic effect on performance.
• Don't use ILM to remotely access data sources and targets across slow or unreliable communications links (branch offices, floating platforms and so on). Instead, stage the data locally and use a separate transfer mechanism (e.g. SFTP).
• Schedule operations so that only one synchronisation operation is occurring at a time. Microsoft ILM will quite happily handle multiple simultaneous imports and exports, but performing simultaneous synchronisation operations will significantly impact its performance.
• Make sure that the ILM application database is set the Simple recovery mode and the logs are frequently truncated (for example, by taking a backup of the database). Because of the way in which ILM commits many small transactions for each record operation, the logs fill quickly and the use of any of the more comprehensive recovery modes  will quickly swamp database resources and lead to a dramatic drop in performance.
• Size the platform carefully. Microsoft ILM requires two processors and 4GB of memory for efficient operation. It also requires very fast discs: consider using directly attached storage and RAID striping. If collocating the SQL Server application database, increase the system memory to 8GB.
• Optimise your Identity Manegement (IM) design to minimise record churn and to ensure that all operations are performed as deltas. Full synchronisations are expensive and can take days to accomplish when many millions of records are involved.