From 504d7ea261ebb5ca0d7542628d2ed6642ad31f53 Mon Sep 17 00:00:00 2001
From: Howard Chu <hyc@openldap.org>
Date: Mon, 8 Nov 2004 04:23:37 +0000
Subject: [PATCH] Assist in cache debugging

---
 servers/slapd/back-bdb/back-bdb.h  |  7 +++++++
 servers/slapd/back-bdb/cache.c     | 20 ++++++++++++--------
 servers/slapd/back-bdb/delete.c    |  2 +-
 servers/slapd/back-bdb/proto-bdb.h |  2 +-
 4 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/servers/slapd/back-bdb/back-bdb.h b/servers/slapd/back-bdb/back-bdb.h
index 40227ccd9e..115b9e532b 100644
--- a/servers/slapd/back-bdb/back-bdb.h
+++ b/servers/slapd/back-bdb/back-bdb.h
@@ -124,6 +124,13 @@ typedef struct bdb_entry_info {
 typedef struct bdb_cache {
 	int             c_maxsize;
 	int             c_cursize;
+	int		c_eiused;
+/* c_eiused shows how many EntryInfos are in use. It should
+ * also equal the length of the LRU list, i.e., everything now lives
+ * on the LRU list. c_cursize shows how many Entries are attached.
+ * c_cursize will be <= c_eiused because internal nodes of the DIT
+ * will be retained in memory as long as their children are in use.
+ */
 	EntryInfo	c_dntree;
 	EntryInfo	*c_eifree;	/* free list */
 	Avlnode         *c_idtree;
diff --git a/servers/slapd/back-bdb/cache.c b/servers/slapd/back-bdb/cache.c
index 48758333e8..a0e436d87e 100644
--- a/servers/slapd/back-bdb/cache.c
+++ b/servers/slapd/back-bdb/cache.c
@@ -244,6 +244,7 @@ bdb_entryinfo_add_internal(
 		ei->bei_rdn.bv_val = NULL;
 #endif
 	} else {
+		bdb->bi_cache.c_eiused++;
 		ber_dupbv( &ei2->bei_nrdn, &ei->bei_nrdn );
 		avl_insert( &ei->bei_parent->bei_kids, ei2, bdb_rdn_cmp,
 			avl_dup_error );
@@ -438,6 +439,7 @@ hdb_cache_find_parent(
 		} else {
 			ei2 = &bdb->bi_cache.c_dntree;
 		}
+		bdb->bi_cache.c_eiused++;
 		ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock );
 
 		/* Got the parent, link in and we're done. */
@@ -567,7 +569,7 @@ bdb_cache_lru_add(
 				 */
 				} else {
 					bdb_cache_delete_internal( &bdb->bi_cache, elru, 0 );
-					bdb_cache_delete_cleanup( &bdb->bi_cache, elru->bei_e );
+					bdb_cache_delete_cleanup( &bdb->bi_cache, elru );
 
 					/* break the loop, unsafe to muck with more than one */
 					elprev = NULL;
@@ -1044,13 +1046,13 @@ bdb_cache_delete(
 void
 bdb_cache_delete_cleanup(
 	Cache *cache,
-	Entry *e )
+	EntryInfo *ei )
 {
-	EntryInfo *ei = BEI(e);
-
-	ei->bei_e = NULL;
-	e->e_private = NULL;
-	bdb_entry_return( e );
+	if ( ei->bei_e ) {
+		ei->bei_e->e_private = NULL;
+		bdb_entry_return( ei->bei_e );
+		ei->bei_e = NULL;
+	}
 
 	free( ei->bei_nrdn.bv_val );
 	ei->bei_nrdn.bv_val = NULL;
@@ -1106,9 +1108,11 @@ bdb_cache_delete_internal(
 		return rc;
 	}
 
+	cache->c_eiused--;
+
 	/* lru */
 	LRU_DELETE( cache, e );
-	cache->c_cursize--;
+	if ( e->bei_e ) cache->c_cursize--;
 
 	/* free cache write lock */
 	ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
diff --git a/servers/slapd/back-bdb/delete.c b/servers/slapd/back-bdb/delete.c
index 33924d4070..234c5feb3f 100644
--- a/servers/slapd/back-bdb/delete.c
+++ b/servers/slapd/back-bdb/delete.c
@@ -574,7 +574,7 @@ done:
 	if( e != NULL ) {
 		if ( rs->sr_err == LDAP_SUCCESS ) {
 			/* Free the EntryInfo and the Entry */
-			bdb_cache_delete_cleanup( &bdb->bi_cache, e );
+			bdb_cache_delete_cleanup( &bdb->bi_cache, BEI(e) );
 		} else {
 			bdb_unlocked_cache_return_entry_w(&bdb->bi_cache, e);
 		}
diff --git a/servers/slapd/back-bdb/proto-bdb.h b/servers/slapd/back-bdb/proto-bdb.h
index 13bc550a54..8f7273f6ec 100644
--- a/servers/slapd/back-bdb/proto-bdb.h
+++ b/servers/slapd/back-bdb/proto-bdb.h
@@ -490,7 +490,7 @@ int bdb_cache_delete(
 );
 void bdb_cache_delete_cleanup(
 	Cache	*cache,
-	Entry	*e
+	EntryInfo *ei
 );
 void bdb_cache_release_all( Cache *cache );
 void bdb_cache_delete_entry(
-- 
2.39.5