From: hno <>
Date: Wed, 3 May 2000 00:35:09 +0000 (+0000)
Subject: hno squid-2.2.STABLE3.nonhierarchical_direct-2.patch
X-Git-Tag: SQUID_3_0_PRE1~2031
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=168dfda9c5d2ca01491d34fcbc3266ab338db4d4;p=thirdparty%2Fsquid.git

hno squid-2.2.STABLE3.nonhierarchical_direct-2.patch
Squid-2.2.STABLE3: nonhierarchical_direct squid.conf directive

New squid.conf directive: nonhierachical_direct. This controls if
requests Squid classifies as non-hierarchical (matches
hierarchy_stoplist or non-cachable request type) should go direct if
possible, or if parents should be used on such requests. Also improved
parent selection for never_direct to try to selects all available parents
to increase the likelyhood that there is at least one alive parent where
the request can be forwarded.
---

diff --git a/src/cf.data.pre b/src/cf.data.pre
index 9d1048dcdf..2d9c1b5c27 100644
--- a/src/cf.data.pre
+++ b/src/cf.data.pre
@@ -1,6 +1,6 @@
 
 #
-# $Id: cf.data.pre,v 1.168 2000/03/14 22:59:13 wessels Exp $
+# $Id: cf.data.pre,v 1.169 2000/05/02 18:35:09 hno Exp $
 #
 #
 # SQUID Internet Object Cache  http://squid.nlanr.net/Squid/
@@ -3030,19 +3030,42 @@ DOC_START
 	encrypted.  This is the encryption key.
 DOC_END
 
+NAME: nonhierarchical_direct
+TYPE: onoff
+LOC: Config.onoff.nonhierarchical_direct
+DEFAULT: on
+DOC_START
+	By default, Squid will send any non-hierarchical requests
+	(matching hierarchy_stoplist or not cachable request type) direct
+	to origin servers.
+
+	If you set this to off, then Squid will prefer to send these
+	requests to parents.
+
+	Note that in most configurations, by turning this off you will only
+	add latency to these request without any improvement in global hit
+	ratio.
+
+	If you are inside an firewall then see never_direct instead of
+	this directive.
+
+nonhierarchical_direct on
+DOC_END
+
 NAME: prefer_direct
 TYPE: onoff
 LOC: Config.onoff.prefer_direct
-DEFAULT: on
+DEFAULT: off
 DOC_START
-	By default, if the ICP, HTCP, Cache Digest, etc. techniques
-	do not yield a parent cache, Squid gives higher preference
-	to forwarding the request direct to origin servers, rather
-	than selecting a parent cache anyway.
+	Normally Squid tries to use parents for most requests. If you by some
+	reason like it to first try going direct and only use a parent if
+	going direct fails then set this to off.
+
+	By combining nonhierarchical_direct off and prefer_direct on you
+	can set up Squid to use a parent as a backup path if going direct
+	fails.
 
-	If you want Squid to give higher precedence to a parent
-	cache, instead of going direct, then turn this option off.
-prefer_direct on
+prefer_direct off
 DOC_END
 
 NAME: strip_query_terms
diff --git a/src/peer_select.cc b/src/peer_select.cc
index 2ac9dcea42..3bd6233c72 100644
--- a/src/peer_select.cc
+++ b/src/peer_select.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: peer_select.cc,v 1.106 2000/05/02 18:32:41 hno Exp $
+ * $Id: peer_select.cc,v 1.107 2000/05/02 18:35:09 hno Exp $
  *
  * DEBUG: section 44    Peer Selection Algorithm
  * AUTHOR: Duane Wessels
@@ -89,6 +89,7 @@ static void peerGetSomeNeighbor(ps_state *);
 static void peerGetSomeNeighborReplies(ps_state *);
 static void peerGetSomeDirect(ps_state *);
 static void peerGetSomeParent(ps_state *);
+static void peerGetAllParents(ps_state *);
 static void peerAddFwdServer(FwdServer **, peer *, hier_code);
 
 static void
@@ -273,11 +274,23 @@ peerSelectFoo(ps_state * ps)
 	peerGetSomeNeighborReplies(ps);
 	entry->ping_status = PING_DONE;
     }
-    if (Config.onoff.prefer_direct)
+    switch (ps->direct) {
+    case DIRECT_YES:
 	peerGetSomeDirect(ps);
-    peerGetSomeParent(ps);
-    /* Have direct as a last resort if possible.. */
-    peerGetSomeDirect(ps);
+	break;
+    case DIRECT_NO:
+	peerGetSomeParent(ps);
+	peerGetAllParents(ps);
+	break;
+    default:
+	if (Config.onoff.prefer_direct)
+	    peerGetSomeDirect(ps);
+	if (request->flags.hierarchical || !Config.onoff.nonhierarchical_direct)
+	    peerGetSomeParent(ps);
+	if (!Config.onoff.prefer_direct)
+	    peerGetSomeDirect(ps);
+	break;
+    }
     peerSelectCallback(ps);
 }
 
@@ -434,6 +447,35 @@ peerGetSomeParent(ps_state * ps)
     }
 }
 
+/* Adds alive parents. Used as a last resort for never_direct.
+ */
+static void
+peerGetAllParents(ps_state * ps)
+{
+    peer *p;
+    request_t *request = ps->request;
+    /* Add all alive parents */
+    for (p = Config.peers; p; p = p->next) {
+	/* XXX: neighbors.c lacks a public interface for enumerating
+	 * parents to a request so we have to dig some here..
+	 */
+	if (neighborType(p, request) != PEER_PARENT)
+	    continue;
+	if (!peerHTTPOkay(p, request))
+	    continue;
+	debug(15, 3) ("peerGetAllParents: adding alive parent %s\n", p->host);
+	peerAddFwdServer(&ps->servers, p, ANY_OLD_PARENT);
+    }
+    /* XXX: should add dead parents here, but it is currently
+     * not possible to find out which parents are dead or which
+     * simply are not configured to handle the request.
+     */
+    /* Add default parent as a last resort */
+    if ((p = getDefaultParent(request))) {
+	peerAddFwdServer(&ps->servers, p, DEFAULT_PARENT);
+    }
+}
+
 static void
 peerPingTimeout(void *data)
 {
diff --git a/src/structs.h b/src/structs.h
index 42c9b350e7..d25e356512 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -1,6 +1,6 @@
 
 /*
- * $Id: structs.h,v 1.318 2000/05/02 18:32:41 hno Exp $
+ * $Id: structs.h,v 1.319 2000/05/02 18:35:09 hno Exp $
  *
  *
  * SQUID Internet Object Cache  http://squid.nlanr.net/Squid/
@@ -407,6 +407,7 @@ struct _SquidConfig {
 	int offline;
 	int redir_rewrites_host;
 	int prefer_direct;
+	int nonhierarchical_direct;
 	int strip_query_terms;
 	int redirector_bypass;
 	int ignore_unknown_nameservers;