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diff --git a/chromium/docs/website/site/throttling/index.md b/chromium/docs/website/site/throttling/index.md deleted file mode 100644 index abd46d7ed7b..00000000000 --- a/chromium/docs/website/site/throttling/index.md +++ /dev/null @@ -1,62 +0,0 @@ ---- -breadcrumbs: [] -page_name: throttling -title: Anti-DDoS HTTP Throttling of Extension-Originated Requests ---- - -Chrome 20 and later implements a mechanism that is intended to prevent -distributed denial of service (DDoS) attacks from being perpetrated, maliciously -or accidentally, by extensions running within Chrome. Chrome 12 through 19 had a -different flavor of this feature, see -[here](/throttling/anti-ddos-http-throttling-in-older-versions-of-chrome). - -To disable the feature, which may be useful for some extension developers: Pass -the **--disable-extensions-http-throttling** command-line flag when starting -Chrome. - -The way the mechanism works is, once a few server errors (HTTP error codes 500 -and greater) in a row have been detected for a given URL (minus the query -parameters), Chrome assumes the server is either unavailable or overloaded due -to a DDoS, and denies requests to the same URL for a short period of time. If, -after this period of time, requests keep failing, this "back-off interval" -period is increased using an exponential factor, and so on and so forth until -the maximum back-off interval is reached. It's important to note that failures -due to the throttling itself are not counted as failures that cause the back-off -interval to be increased. - -The back-off delay is calculated as follows: delay = initial_backoff \* -multiply_factor^(effective_failure_count - 1) \* Uniform(1 - jitter_factor, 1\] - -For the canonical details on the back-off parameters used, see -<http://src.chromium.org/viewvc/chrome/trunk/src/net/url_request/url_request_throttler_entry.cc?view=markup>. -What follows is based on the most recent values for these parameters as of this -writing: - -The back-off parameters used in the formula above will (at maximum values, i.e. -without the reduction caused by jitter) add 0-41% (distributed uniformly in that -range) to the "perceived downtime" of the remote server, once exponential -back-off kicks in and is throttling requests for more than about a second at a -time. Once the maximum back-off is reached, the added perceived downtime -decreases rapidly, percentage-wise. - -Another way to put it is that the maximum additional perceived downtime with -these numbers is a couple of seconds shy of 15 minutes, and such a delay would -not occur until the remote server has been actually unavailable at the end of -each back-off period for a total of about 48 minutes. - -Back-off does not kick in until after the first 4 errors, which helps avoid -back-off from kicking in on// flaky connections. To simplify life for web -developers, throttling is never used for URLs that resolve to localhost. - -If you believe your extension may be having problems due to HTTP throttling, you -can try the following: - -1. Pass the **--disable-extensions-http-throttling** command-line flag - when starting Chrome, to see if the problem reproduces with the - feature turned off. -2. With exponential back-off throttling of extension requests turned on - (i.e. **without** the command-line flag above), visit - [chrome://net-internals/#events](javascript:void(0);) and keep it - open while you reproduce the problem you were seeing. Diagnostic - information will be added to the log, which may help you track down - what is happening.
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