Managed Dependencies: fixing cold start time regression #311
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AnatoliB
requested review from
Francisco-Gamino,
SatishRanjan and
eamonoreilly
SatishRanjan
approved these changes
Aug 19, 2019
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When the ManagedDependencies folder contains leftovers from the previous PowerShell worker version, the new PowerShell worker may not be able to detect the correct snapshot to use. As a result, it installs a new snapshot on every PowerShell worker start, causing unnecessary "cold start" delays.
The problem is that the installed snapshot folders are expected to follow the
*rpattern, and some Az.* module names also match this pattern coincidentally (e.g. Az.TrafficManager). As a result, PowerShell worker mistakenly considersManagedDependencies/Az.TrafficManagerthe latest installed snapshot folder, tries to find theManagedDependencies/Az.TrafficManager/Az/2.5.0, assumes this snapshot is not good enough, and starts installing a new one.This change replaces the
*rpattern with*.r, which will filter out all the existing Az.* module folders, so that they don't interfere with looking for the latest snapshot anymore. These folders will be eventually purged from the storage.Until this change is deployed, the workaround for the issue is to stop the app, manually remove the content of the D:\home\data\ManagedDependencies folder, and start the app again.