Abstract: A method includes comparing a first instance with a second instance of a document in a plurality of documents. The first instance is obtained from a remote location at a specified time before the second instance is obtained from the remote location, and (i) the specified time is determined in accordance with a first crawl interval associated with the document, (ii) each document in the plurality of documents is assigned to a tier in a plurality of tiers, each tier having a distinct associated range of web crawl intervals, and (iii) the first crawl interval is assigned a first tier. The method also includes computing a second crawl interval for the document, which is a function of the document comparison; and determining whether the second crawl interval is in the first tier. When the second crawl interval is not, the first document is reassigned to another tier.

Abstract: A method includes comparing a first instance with a second instance of a document in a plurality of documents. The first instance is obtained from a remote location at a specified time before the second instance is obtained from the remote location, and (i) the specified time is determined in accordance with a first crawl interval associated with the document, (ii) each document in the plurality of documents is assigned to a tier in a plurality of tiers, each tier having a distinct associated range of web crawl intervals, and (iii) the first crawl interval is assigned a first tier. The method also includes computing a second crawl interval for the document, which is a function of the document comparison; and determining whether the second crawl interval is in the first tier. When the second crawl interval is not, the first document is reassigned to another tier.

Abstract: A method and system is disclosed for associating an appropriate web crawl interval with a document so that the probability of the document's stale content being used by a search engine is below an acceptable level when the search engine crawls the document at its associated web crawl interval. The web crawl interval of a document is determined through an iterative process and updated dynamically by the search engine after every visit to the document by a web crawler. A multi-tier data structure is employed for managing the web crawl order of billions of documents on the Internet. The search engine may move a document from one tier to another if its web crawl interval is changed significantly.

Abstract: A method and system is disclosed for associating an appropriate web crawl interval with a document so that the probability of the document's stale content being used by a search engine is below an acceptable level when the search engine crawls the document at its associated web crawl interval. The web crawl interval of a document is determined through an iterative process and updated dynamically by the search engine after every visit to the document by a web crawler. A multi-tier data structure is employed for managing the web crawl order of billions of documents on the Internet. The search engine may move a document from one tier to another if its web crawl interval is changed significantly.

Abstract: A method and system is disclosed for associating an appropriate web crawl interval with a document so that the probability of the document's stale content being used by a search engine is below an acceptable level when the search engine crawls the document at its associated web crawl interval. The web crawl interval of a document is determined through an iterative process and updated dynamically by the search engine after every visit to the document by a web crawler. A multi-tier data structure is employed for managing the web crawl order of billions of documents on the Internet. The search engine may move a document from one tier to another if its web crawl interval is changed significantly.