This post is intended to provide information about finding SSSD bottlenecks with SystemTap. One of the most common complaints with SSSD is slowness during login or NSS commands such as ‘getent’ or ‘id’ especially in large LDAP/Active Directory environments. Log analysis alone can be difficult to track down the source of the delay, especially with certain configurations(Indirect AD Integration) where there is a significant number of backend operations that occur during login. In SSSD 1.14, performance enhancements were made to optimize cache write operations decreasing overall time spent updating the filesystem cache. These bottlenecks were discovered by developers based on userspace probing in certain areas of the SSSD code with SystemTap. Below are some steps on getting started with SystemTap and SSSD, in this example we will use recent additions of High-Level Data Provider request probes. First, install the necessary packages mentioned here: Installation and Setup It is not r...