... HTTP Headers for Optimal Performance In http_protocol.c, the Date header is set according to $r->request_time. A mod_ perlscript can read, but not change,$r->request_time.Last-Modified HeaderSection ... Associates, Inc. All rights reserved.540|Chapter 16: HTTP Headers for Optimal Performance lots of requests to retrieve the same content before it changes again, and if it is muchcheaper to test whether ... to cooperate with caches toincrease the performance of the site can provide significant benefits. If Squid or mod_ proxy is used in httpd accelerator mode (as discussed in Chapter 12), it is...