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The maximum number of retries before going upstream to parent or origin. This is related to the previous parameter. These settings should only be used if your content is cacheable as otherwise it would just serialize your connections to the origin.

Example: Lets say the typical response times is 50-100ms, try setting proxy.config.http.cache.max_open_read_retries to 3 and proxy.config.http.cache.open_read_retry_time to 50

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