Page tree
Skip to end of metadata
Go to start of metadata

The HistoryBackend consists of a number of components:  

HistoryDatabase

  • Stores past 3 months of history

  • URLDatabase (stores a list of URLs)      
  • DownloadDatabase (stores a list of downloads)      
  • VisitDatabase (stores a list of visits for the URLs)      
  • VisitSegmentDatabase (stores groups of URLs for the most visited view)

ArchivedDatabase

  • Stores history older than 3 months     
  • URLDatabase (stores a list of URLs)      
  • DownloadDatabase (stores a list of downloads)      
  • VisitDatabase (stores a list of visits for the URLs)

      (this does not store visit segments as they expire after 3 months)

TextDatabaseManager

  • Manages multiple text database for different times  
  • TextDatabase (represents a single month of full-text index) 

ExpireHistoryBackend

  •  Manages moving objects from HistoryDatabase to the ArchivedDatabase and deleting

 

Static ConstantValue 
Segment Data Retention90 daysHow long Chrome keeps segment data for in days.  Currently 3 months.
Commit Interval Seconds10 secondsHow long Chrome waits to do a commit, so that things are batched together.
Favicon Refetch Days7 daysThe amount of time before Chrome re-fetches the favicon.
Archive Days Threshold90 daysThe number of days old a history entry can be before it is considered "old" and is archived.