@@ -526,11 +526,9 @@ the application whether or not the cached response is still valid. If the
526526cache *is * still valid, your application should return a 304 status code
527527and no content. This tells the cache that it's ok to return the cached response.
528528
529- Under this model, you mainly save bandwidth as the representation is not
530- sent twice to the same client (a 304 response is sent instead). But if you
531- design your application carefully, you might be able to get the bare minimum
532- data needed to send a 304 response and save CPU also (see below for an implementation
533- example).
529+ Under this model, you only save CPU if you're able to determine that the
530+ cached response is still valid by doing *less * work than generating the whole
531+ page again (see below for an implementation example).
534532
535533..tip ::
536534
@@ -578,10 +576,10 @@ automatically sets the ``Response`` status code to 304.
578576
579577..note ::
580578
581- The ``If-None-Match ``request headerequals the ``ETag `` header of the
582- last response sent to the client for theparticular resource. This is
583- how theclient and server communicate with each other and decide whether
584- or not the resource has been updated since it was cached.
579+ Thecache sets the ``If-None-Match `` headeron therequest to the ``ETag ``
580+ of the original cached response before sending therequest back to the
581+ app. This is how thecache and server communicate with each other and
582+ decide whether or not the resource has been updated since it was cached.
585583
586584This algorithm is simple enough and very generic, but you need to create the
587585whole ``Response `` before being able to compute the ETag, which is sub-optimal.
@@ -646,10 +644,10 @@ the ``Response`` will be set to a 304 status code.
646644
647645..note ::
648646
649- The ``If-Modified-Since ``request headerequals the ``Last-Modified ``
650- header of thelast responsesent to theclient for the particular resource.
651- This is how theclient and server communicate with each other and decide
652- whether or not the resource has been updated since it was cached.
647+ Thecache sets the ``If-Modified-Since `` headeron the request to the ``Last-Modified ``
648+ of theoriginal cached responsebefore sending therequest back to the
649+ app. This is how thecache and server communicate with each other and
650+ decide whether or not the resource has been updated since it was cached.
653651
654652..index ::
655653 single: Cache; Conditional get