High-performance Crawler need Scalable Parallel, distributed Fast a Bottleneck? Network utilization Polite 口DoS, robot txt Robust o Traps, errors, crash recovery ■ Continuous 口 Batch or incrementa
High-performance Crawler need… Scalable Parallel , distributed Fast Bottleneck? Network utilization Polite DoS, robot.txt Robust Traps, errors, crash recovery Continuous Batch or incremental
Caching DNs Async UDP (slack about 大规模爬取器的一种结构图 DNS prefetch K expiry dates client DNS Text indexing resolver nd other repository DNS client (UDP) analyses index cache 三 Hyperin Http extractor until Http send normalizer DNS Socket available receive Per-server queues Page fetching context/thread MisPageKnown? x 28 Crawl meta-data Load monitor Persistent URL work-thread global work isUrlVisited? approval manager pool of URLs guard
大规模爬取器的一种结构图