原因:download_delay设置得过大,导致爬虫整体运行效率低下。 解决方法:适当减小download_delay的值,或者采用随机延迟策略,在保证不被封禁的前提下提高效率。 问题2:仍然被目标网站封禁 原因:即使设置了download_delay,爬虫的行为可能仍然触发了目标网站的反爬虫机制。
download_delay对爬虫性能有何影响? download_delay是一个在网络爬虫(Web Crawler)中常用的参数,它用于控制爬虫在连续下载网页之间的等待时间。这个参数的主要目的是减少对目标网站服务器的压力,防止因爬虫访问过于频繁而被封禁。 基础概念 download_delay是一个时间间隔(通常以秒为单位),设置在爬虫的两个连续请求之间。
DOWNLOAD_DELAY 会影响 CONCURRENT_REQUESTS,不能使并发显现出来。 思考: 当有CONCURRENT_REQUESTS,没有DOWNLOAD_DELAY 时,服务器会在同一时间收到大量的请求。 当有CONCURRENT_REQUESTS,有DOWNLOAD_DELAY 时,服务器不会在同一时间收到大量的请求。
Resolves #5083 Document how DOWNLOAD_DELAY affects per-domain concurrency 34e4ed7 codecov bot commented Jun 21, 2022 • edited Codecov Report Merging #5540 (f87d061) into master (604ddf8) will not change coverage. The diff coverage is n/a. @@ Coverage Diff @@ ## master #5540 +...
Top Abstract Download delay is the amount of time needed for instructional materials to appear on a Web page on the client computer after the page is accessed from the server; it is a new challenge specific to designing and using Internet-based materials (Davis & Hantula, 2001). Also known...
Hello Everyone, I am trying to boot up WINEC7 on DM8148 custom board (The custom board has 2GB DDR and the required changes have been done to the source files),though i am able to boot the board with WINEC7 , i have a problem while booting up ,There is a delay of ...
The above image demonstrates the effects of the tick delay when using an "Instant Mine" tool, when in creative mode, and when using an Efficiency V tool. In vanilla Minecraft, the default delay is 5 ticks, except with instant mine tools where the delay is 0 ticks.See the minecraft wiki...
The present study investigated the effects of a variable unique to Internet-based learning; download delay of instructional materials. A simulated online teaching tool was created to measure the effects of download delay of images on test performance, time spent on the material, end-user satisfaction...
I’ve been experiencing an issue where, during the download process, there is a delay of several seconds to minutes at certain stages, and I can't seem to pinpoint why it happens. The waiting phase seems to be intermittent—sometimes it occurs, sometimes it doesn’t. ...
Network Delay Simulator (netsimgui.exe) free download, Network Delay Simulator tool allows you to perform network...