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CONFIG proxy.config.reverse_proxy.enabled INT 0
CONFIG proxy.config.url_remap.remap_required INT 0

Reverse Proxy Object Expiration Fuzzy Logic

Step 2 – Configure

You may or may not wish to enable these configuration options.
They essentially make ATS more aggressive in caching than its default configuration would allow.

HTTP Background Fill Completion

There's an algorithm here that I don't fully understand, but this setting should guarantee that objects
loaded in the background are cached regardless of their size.

From Leif H: This recommendation is wrong, it should be set to 0.0 for it to always kick in. It allows the server to continue fetching / caching a large object even if the client disconnects. This setting (with a value of 0.0) is a prerequisite for getting read-while-writer to kick in.

CONFIG proxy.config.http.background_fill_completed_threshold FLOAT 0.000000

Fuzzy Object Expiration Logic

From Leif H: As described here, is not what it does, at all. Fuzzy logic is there to allow (random chance) a client to go to origin before the object is stale in cache. The idea is that you would (for some reasonably active objects) prefetch the object such that you always have it fresh in cache.

An interesting notion, but not one I desire. I had to dig into the codebase for this one. Apparently this is a feature designed for reverse proxies
to "sweep" the cache at defined intervals. My memory's a bit foggy, so apologies if I got the definition wrong.
In any case, this functionality doesn't help a forward proxy cache whose goal is to keep objects in the cache.
The following setting disables this feature.

CONFIG proxy.config.http.cache.fuzz.min_time INT 0

Step

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3 – Optimize

CPU Cores (also multiple CPUs)

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CONFIG proxy.config.http.keep_alive_no_activity_timeout_in INT 115
CONFIG proxy.config.http.keep_alive_no_activity_timeout_out INT 115
CONFIG proxy.config.http.transaction_no_activity_timeout_in INT 90
CONFIG proxy.config.http.transaction_no_activity_timeout_out INT 90
CONFIG proxy.config.http.transaction_active_timeout_in INT 43200
CONFIG proxy.config.http.transaction_active_timeout_out INT 43200
CONFIG proxy.config.http.accept_no_activity_timeout INT 30

HTTP Background Fill Competion

There's an algorithm here that I don't fully understand, but this setting should guarantee that objects
loaded in the background are cached regardless of their size.

CONFIG proxy.config.http.background_fill_completed_threshold FLOAT 1.000000

HTTP Cache Options

The following settings are pretty important. I'll go through them one at a time.

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