Transport optimizer plugin
From B2evolution
The Transport optimizer plugin helps you saving bandwidth.
It supports ETag headers and GZip compression.
Contents |
[edit] ETag headers
With every generated page, a hash value of the content gets send to the browser. If a browser then requests the same URL again, it may send this hash value again. If it has not changed since then, we can send a "304 Not Modified" response, without transferring the content again.
NOTE: this does not save processing of the page - it still gets generated.
[edit] GZip compression
If enabled and the browser supports it, the generated page content gets compressed.
This saves bandwidth, but needs more processing power on the server.
NOTE: it's better to let the webserver handle compression, e.g. through Apache's mod_gzip.
[edit] General note
For all these features, we need PHP output buffering, which will prevent from sending the output progressively to the webserver.
If a long page takes 2 seconds to be generated completely on a loaded server, the top of the page will only be sent after those 2 seconds, and the user won't see anything during at least 2 seconds (generation + transmission time). Without output buffering, the output will be sent progressively starting at 0 seconds (given that there's nearly no initialisation on a page) and the user will start seeing something earlier (0 + transmission time).
[edit] Location
The Transport optimizer plugin gets shipped with b2evolution and can be found in /blogs/plugins/_transport_optimizer.plugin.php.