- much better processing of only-if-cached (not extensively tested though)

- many additions to UpdateCounters (under-construction)

diff --git a/src/client_side.cc b/src/client_side.cc
index 55d9c8644cf1091e88ba0e21bf69445c9fcd108c..73d95c5ff9ea57e4d78b30a46994a527cb5c5206 100644 (file)
--- a/src/client_side.cc
+++ b/src/client_side.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: client_side.cc,v 1.259 1998/04/07 22:37:44 wessels Exp $
+ * $Id: client_side.cc,v 1.260 1998/04/07 23:40:34 rousskov Exp $
  *
  * DEBUG: section 33    Client-side Routines
  * AUTHOR: Duane Wessels
@@ -57,6 +57,7 @@ static RH clientRedirectDone;
 static STCB clientHandleIMSReply;
 static int clientGetsOldEntry(StoreEntry * new, StoreEntry * old, request_t * request);
 static int checkAccelOnly(clientHttpRequest *);
+static int clientOnlyIfCached(clientHttpRequest * http);
 static STCB clientSendMoreData;
 static STCB clientCacheHit;
 static void clientParseRequestHeaders(clientHttpRequest *);
@@ -107,6 +108,23 @@ clientAccessCheck(void *data)
     aclNBCheck(http->acl_checklist, clientAccessCheckDone, http);
 }
 
+/*
+ * returns true if client specified that the object must come from the cache
+ * witout contacting origin server
+ */
+static int
+clientOnlyIfCached(clientHttpRequest * http)
+{
+    const request_t *r = http->request;
+    assert(r);
+    if (EBIT_TEST(r->flags, REQ_CC_ONLY_IF_CACHED)) {
+       /* future interface: 
+        * if (r->cache_control && EBIT_TEST(r->cache_control->mask, CC_ONLY_IF_CACHED)) { */
+       return 1;
+    } else
+       return 0;
+}
+
 static HttpReply *
 clientConstructProxyAuthReply(clientHttpRequest * http)
 {
@@ -228,6 +246,15 @@ clientProcessExpired(void *data)
     char *url = http->uri;
     StoreEntry *entry = NULL;
     debug(33, 3) ("clientProcessExpired: '%s'\n", http->uri);
+    /*
+     * check if we are allowed to contact other servers
+     * @?@: Instead of a 504 (Gateway Timeout) reply, we may want to return 
+     *      stale entry *if* it matches client requirements
+     */
+    if (clientOnlyIfCached(http)) {
+       clientProcessOnlyIfCachedMiss(http);
+       return;
+    }
     EBIT_SET(http->request->flags, REQ_REFRESH);
     http->old_entry = http->entry;
     entry = storeCreateEntry(url,
@@ -491,8 +518,8 @@ clientUpdateCounters(clientHttpRequest * http)
 {
     int svc_time = tvSubMsec(http->start, current_time);
     icp_ping_data *i;
-#if CACHE_DIGEST
-    char *t;
+#if SQUID_PEER_DIGEST
+    const HttpReply *reply = NULL;
 #endif
     Counter.client_http.requests++;
     kb_incr(&Counter.client_http.kbytes_in, http->req_sz);
@@ -529,27 +556,35 @@ clientUpdateCounters(clientHttpRequest * http)
     i = &http->request->hier.icp;
     if (0 != i->stop.tv_sec && 0 != i->start.tv_sec)
        statHistCount(&Counter.icp.query_svc_time, tvSubUsec(i->start, i->stop));
-#if CACHE_DIGEST
-    assert(http->request->hier.used_icp + http->request->hier.used_cd < 2);
-    if (http->request->hier.used_icp) {
+#if SQUID_PEER_DIGEST
+    if (http->request->hier.alg == PEER_SA_ICP) {
        statHistCount(&Counter.icp.client_svc_time, svc_time);
        Counter.icp.times_used++;
-    }
-    if (http->request->hier.used_cd) {
+    } else
+    if (http->request->hier.alg == PEER_SA_DIGEST) {
        statHistCount(&Counter.cd.client_svc_time, svc_time);
        Counter.cd.times_used++;
-    }
-    t = httpHeaderGetLastStr(, HDR_X_CACHE);
-    if (NULL != t && 0 == strncmp(t, "HIT", 3)) {
-       if (http->request->hier.cd_hit)
-           Counter.cd.true_hits++;
-       else
-           Counter.cd.false_miss++;
     } else {
-       if (http->request->hier.cd_hit)
-           Counter.cd.false_hit++;
+       assert(http->request->hier.alg == PEER_SA_NONE);
+    }
+    if (/* we used ICP or CD for peer selecton */
+       http->request->hier.alg != PEER_SA_NONE &&
+       /* a CD lookup found peers with digests */
+       http->request->hier.cd_lookup != LOOKUP_NONE &&
+       /* paranoid: we have a reply pointer */
+       (reply = storeEntryReply(http->entry))) {
+       const char *x_cache_fld = httpHeaderGetLastStr(&reply->header, HDR_X_CACHE);
+       const int real_hit = x_cache_fld && !strncmp(x_cache_fld, "HIT", 3);
+       const int guess_hit = http->request->hier.cd_lookup == LOOKUP_HIT;
+       peer *peer = peerFindByName(http->request->hier.host);
+
+       cacheDigestGuessStatsUpdate(&Counter.cd.guess_stats,
+           real_hit, guess_hit);
+       if (peer)
+           cacheDigestGuessStatsUpdate(&peer->digest.stats.guess,
+               real_hit, guess_hit);
        else
-           Counter.cd.true_miss++;
+           debug(33,1) ("clientUpdateCounters: lost peer: %s!\n", storeUrl(http->entry));
     }
 #endif
 }
@@ -1386,7 +1421,6 @@ clientProcessRequest(clientHttpRequest * http)
        storeClientListAdd(entry, http);
     }
     http->out.offset = 0;
-    /* "pure" hit? (will not contact other servers) */
     switch (http->log_type) {
     case LOG_TCP_HIT:
     case LOG_TCP_NEGATIVE_HIT:
@@ -1403,19 +1437,6 @@ clientProcessRequest(clientHttpRequest * http)
            clientCacheHit,
            http);
        return;
-    default:
-       break;
-    }
-    /* ok, it is a miss or a "dirty" hit (will contact other servers) */
-    /* note: bug: LOG_TCP_IMS_MISS may result in a "pure" hit @?@ */
-    /* are we allowed to contact other servers? */
-    if (EBIT_TEST(r->flags, REQ_CC_ONLY_IF_CACHED)) {
-       /* future interface: if (r->cache_control && EBIT_TEST(r->cache_control->mask, CC_ONLY_IF_CACHED)) { */
-       /* nope, bailing out */
-       clientProcessOnlyIfCachedMiss(http);
-       return;
-    }
-    switch (http->log_type) {
     case LOG_TCP_IMS_MISS:
        if (entry->store_status == STORE_ABORTED)
            debug(33, 0) ("clientProcessRequest 2: entry->swap_status == STORE_ABORTED\n");
@@ -1462,6 +1483,13 @@ clientProcessMiss(clientHttpRequest * http)
        storeUnlockObject(http->entry);
        http->entry = NULL;
     }
+    /*
+     * Check if client tolerates misses
+     */
+    if (clientOnlyIfCached(http)) {
+       clientProcessOnlyIfCachedMiss(http);
+       return;
+    }
     /*
      * Check if this host is allowed to fetch MISSES from us (miss_access)
      */
@@ -1770,7 +1798,7 @@ clientReadRequest(int fd, void *data)
            comm_close(fd);
            return;
        } else if (conn->in.offset == 0) {
-           debug(50, 2) ("clientReadRequest: FD %d: no data to process\n", fd);
+           debug(50, 2) ("clientReadRequest: FD %d: no data to process (%s)\n", fd, xstrerror());
            return;
        }
        /* Continue to process previously read data */