These are the highlights of new features or additions to existing features in v5.0.x and 5.1.x. For the complete list of all changes see this JIRA Release Notes.

General Changes

Some changes have been made to the HostDB data structures. The defaults configurations that ships with ATS v6.x still works, but if you have made changes to either of these configurations, you might have to modify them. Specifically, you might have to either reduce the number of entries supported, or, increase the storage size.

CONFIG proxy.config.hostdb.size INT 120000
CONFIG proxy.config.hostdb.storage_size INT 45375488

Jira: TS-4207

New configuration options

• Limits proxy.config.http.origin_max_connections_queue limits the number of requests to be queued when the proxy.config.http.origin_max_connections is reached.
• Two new timeouts are available for WebSockets: proxy.config.httpwebsocket.origin_max_connections_queueno_activity_timeout and proxy.config.websocket.active_timeout.
• The congestion control algorithm used is now configurable for both incoming, and outbound connections, via proxy.config.net.tcp_congestion_control_in and proxy.config.net.tcp_congestion_control_out.

Jira: TS-4341, TS-3922, TS-4064,Jira: 

TLS

 We continue to improve our TLS (HTTPS) features and support. Noteworthy in 5.2.x is:

...

Jira: TS-3153, TS-2503, TS-2417, TS-2956, TS-3080, TS-3127

traffic_line

• traffic_line -m is now using an unachored regular expression, similar to how diagnostic tracers work.
• traffic_line --backtrace will produce a stack backtrace for all running threads.

Jira: TS-3034, TS-3145

traffic_layout

A new command line utility, traffic_layout, is now available. This will show the layout and configuration option for the ATS build tree.

Jira: TS-3041

traffic_via

This is a new command line tool, to parse and decipher the Via: header that Traffic Server can produce. This is useful for debugging e.g. cache results etc.

Jira: TS-3149

traffic_crashlog

This is the helper application around the new crash logging feature. For more information, see the documentation.

Jira: TS-3195

Plugin Improvements

The following plugins have new features and improvements.

header_rewrite

• We now support variable expansion in the set-redirect operator.
• You can now do matching operators on the port.
• We do not need Boost.

Jira: TS-2955, TS-3108, TS-3068

stats_over_http

This plugin will now emit JSON numbers.

Jira: TS-3071

background_fetch

• The plugin behavior and activation can now be controlled per remap-rule.
• You an control the behavior based on content type.

Jira: TS-2682, TS-2683

Plugin APIs

The following additions were made to the plugin APIs:

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