FIT 14.4: Web Accelerator Update

This release brings a performance update to the “rear side”. When communicating with an origin server, a TCP connection needs to be established. This comprises multiple round trips. For encrypted connections (HTTPS), an additional TLS handshake is necessary to setup parameters for secure communication. Depending on the network latency this adds up to a significant amount of waiting time in the critical path. Furthermore, the throughput of a freshly established TCP connection is limited. Only after a number of network packages have been exchanged, the throughput increases.

With 14.4, we start recycling TCP connections to avoid these performance penalties. This reduces connection overhead and improves request performance. The savings are especially high for TLS backends and (very) remote origins. On our production systems we have seen average speed-ups of up to 20%. But even in low latency environments with plain HTTP there are some milliseconds to scrape. Check your fit_request.log to see what’s in it for you!

Besides that, we have fixed a number of bugs. But in case something goes wrong nevertheless, you can now fail with grace with a custom error page.

Please note that this major release includes deprecations and removals.

In the Beta section we have introduced a page cache for PPL: When navigating back and forth in the browser history, no HTTP request or HTML parsing will be required. Instead, the previous pages’ DOM objects may be reused, resulting in much faster and less interruptive history navigation.

Refer to the full changelog for a more detailed list of changes.