Cache invalidation technique with spurious resource change indications
US6912562B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 2003 |
| Grant date | Jun 28, 2005 |
| Priority date | — |
| Expiry date | Oct 11, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L69/329
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A Web server maintains, for one or more resources, a respective list of clients who requested that resource. The server takes on the responsibility of notifying all of those clients on when the resource in question changes, thereby letting them know that if the resource is again asked for by a user, an updated copy will have to be requested from the origin server. The server thereupon purges the client list, and then begins rebuilding it as subsequent requests come in for the resource in question. Invalidation messages are sent to selected “victim” clients on the client list, independent of whether the resource in question has changed, when the list meets a predetermined criterion, such as becoming too large. The victim clients may include clients who access the server less frequently than others, clients who have accessed the server in the more distant past than other clients, i.e., using a first-in-first methodology, or clients who have not subscribed to a service that keeps them from being victim clients. Review of a client list to determine whether it meets the selected criterion can be invoked every time a client gets added to a client list or on a scheduled basis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.