AVEVA Historian processes

AVEVA Historian Client Access Point (aahClientAccessPoint)

aahClientAccessPoint.exe

Manages communication from HCAL clients to the Historian . For more information, see Configure data acquisition.

AVEVA Historian Configuration (InSQLConfiguration)

aahCfgSvc.exe

Handles all configuration requests, as well as hosts the interfaces for manual data input and retrieval. For more information, see About the configuration subsystem.

AVEVA Historian Event Storage Process

aahEventStorage.exe

Manages the storage of alarms and events to history blocks.

AVEVA Historian Classic Event System (InSQLEventSystem)

aahEventSvc.exe

Searches through history data and determines if specific events have occurred. For more information, see Classic event subsystem.

AVEVA Historian Indexing (InSQLIndexing)

aahIndexSvc.exe

Manages the internal indexing of history data that was stored by AVEVA Historian prior to 2014 R2.

AVEVA Historian IOServer

aahIDataService.exe

Provides realtime data values from the Historian to network clients using an iData-compliant protocol. For more information, see the AVEVA Historian Retrieval Guide.

AVEVA Historian IOServer (classic) (InSQLIOServer)

aahIOSvrSvc.exe

Provides realtime data values from the Historian to network clients using the SuiteLink protocol. For more information, see the AVEVA Historian Retrieval Guide.

Data Import Subsystem (InSQLManualStorage)

aahManStSvc.exe

Accepts incoming data from CSV files and store-and-forward history blocks from Classic IDASs (shipped with AVEVA Historian prior to 2017). Stores the data in history blocks.

AVEVA Historian OData/REST web service

aahOWINHostLocal.exe

Retrieves alarm and event data from history block storage.

Classic Data Redirector Subsystem (InSQLStorage)

aahStoreSvc.exe

Accepts incoming real-time data from Classic IDASs and redirects it to AVEVA Historian storage.

AVEVA Historian Storage Process

aahStorage.exe

Storage process. Accepts incoming plant data and stores it to history blocks. Not a system service. For more information, see About data storage.

AVEVA Historian System Driver (InSQLSystemDriver)

aahDrvSvc.exe

Generates data values for various system monitoring tags. For more information, see About system driver and system tags.

AVEVA Historian Metadata Server

aahMetadataServer.exe

Maintains the tag metadata cache for tags stored by the storage process. Not a system service.

AVEVA Historian Search

HistorianSearch-x64.exe

Search process. Used to store and retrieve tags, saved content and keywords.

Note: The search process has a fixed minimum overhead of 500 MB of memory usage. If a large number of tags are involved in a search, it is not unusual for the process to consume up to 1 GB of memory.