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NOTE: This setting should be sized relative to the amount of memory you want to use.
Also, it requires restarting ATS to properly take effect.

Disk Target Fragment Size

This setting defines the optimal fragment size when storing objects to disk.  I noticed a considerable performance improvement when changing this from its default.  Please be aware I'm not sure if this setting willl scale properly, but works well for me.

CONFIG proxy.config.cache.target_fragment_size INT 262144

NOTE: This setting requires clearing the disk cache and restarting ATS to properly take effect.

Cache Minimum Average Object Size

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The default config for ATS leaves enables some buffering between ATS and the client.  I eventually decided While this simply isn't necessary, I eventually decided on the following settings.  Combined with other performance tweaks, these work well overall.

CONFIG proxy.config.net.sock_send_buffer_size_in INT 064K
CONFIG proxy.config.net.sock_recv_buffer_size_in INT 08K
CONFIG proxy.config.net.sock_send_buffer_size_out INT 08K
CONFIG proxy.config.net.sock_recv_buffer_size_out INT 064K

Step 4 - Secure

Maximum Inbound Concurrent Connections

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