About data storage subsystem processes

The Data Storage subsystem consists of one or more processes named aahStorage.exe. The Main and Auto-Summary storage instances are child processes. Therefore, in the Windows Task Manager you can see several instances of the aahStorage.exe process that are differentiated by their command lines.

The Storage subsystem is available in 32 and 64-bit versions. If you install AVEVA Historian on a 64-bit operating system, the Storage subsystem always runs as native 64-bit application. However, if an AVEVA Application Server engine was deployed in a 32-bit mode, the store-and-forward storage engine on that computer will also be 32-bit if there was no prior Historian installation on the computer. The Storage subsystem also includes the Metadata Server process (aahMetadataServer.exe) responsible for caching Storage tag metadata persisted in the Runtime database.

The Classic Data Redirector service (aahStoreSvc.exe) is responsible for redirecting to storage any streamed data coming from classic IDASs (version 2014 R2 or earlier) and the system driver. The aahManStSvc.exe service handles data that is imported from CSV files and store-and-forward data from IDASs from version 2014 R2 or earlier.