diff --git a/include/mpool.h b/include/mpool.h
index 0f08e8dab7b7..1adf60d5383b 100644
--- a/include/mpool.h
+++ b/include/mpool.h
@@ -51,8 +51,8 @@
 
 /* The BKT structures are the elements of the queues. */
 typedef struct _bkt {
-	CIRCLEQ_ENTRY(_bkt) hq;		/* hash queue */
-	CIRCLEQ_ENTRY(_bkt) q;		/* lru queue */
+	TAILQ_ENTRY(_bkt) hq;		/* hash queue */
+	TAILQ_ENTRY(_bkt) q;		/* lru queue */
 	void    *page;			/* page */
 	pgno_t   pgno;			/* page number */
 
@@ -62,9 +62,9 @@ typedef struct _bkt {
 } BKT;
 
 typedef struct MPOOL {
-	CIRCLEQ_HEAD(_lqh, _bkt) lqh;	/* lru queue head */
+	TAILQ_HEAD(_lqh, _bkt) lqh;	/* lru queue head */
 					/* hash queue array */
-	CIRCLEQ_HEAD(_hqh, _bkt) hqh[HASHSIZE];
+	TAILQ_HEAD(_hqh, _bkt) hqh[HASHSIZE];
 	pgno_t	curcache;		/* current number of cached pages */
 	pgno_t	maxcache;		/* max number of cached pages */
 	pgno_t	npages;			/* number of pages in the file */
diff --git a/lib/libc/db/mpool/mpool.c b/lib/libc/db/mpool/mpool.c
index 29377d30030e..59ed4d3d0ce1 100644
--- a/lib/libc/db/mpool/mpool.c
+++ b/lib/libc/db/mpool/mpool.c
@@ -86,9 +86,9 @@ mpool_open(key, fd, pagesize, maxcache)
 	/* Allocate and initialize the MPOOL cookie. */
 	if ((mp = (MPOOL *)calloc(1, sizeof(MPOOL))) == NULL)
 		return (NULL);
-	CIRCLEQ_INIT(&mp->lqh);
+	TAILQ_INIT(&mp->lqh);
 	for (entry = 0; entry < HASHSIZE; ++entry)
-		CIRCLEQ_INIT(&mp->hqh[entry]);
+		TAILQ_INIT(&mp->hqh[entry]);
 	mp->maxcache = maxcache;
 	mp->npages = sb.st_size / pagesize;
 	mp->pagesize = pagesize;
@@ -142,8 +142,8 @@ mpool_new(mp, pgnoaddr)
 	bp->flags = MPOOL_PINNED;
 
 	head = &mp->hqh[HASHKEY(bp->pgno)];
-	CIRCLEQ_INSERT_HEAD(head, bp, hq);
-	CIRCLEQ_INSERT_TAIL(&mp->lqh, bp, q);
+	TAILQ_INSERT_HEAD(head, bp, hq);
+	TAILQ_INSERT_TAIL(&mp->lqh, bp, q);
 	return (bp->page);
 }
 
@@ -186,10 +186,10 @@ mpool_get(mp, pgno, flags)
 		 * of the lru chain.
 		 */
 		head = &mp->hqh[HASHKEY(bp->pgno)];
-		CIRCLEQ_REMOVE(head, bp, hq);
-		CIRCLEQ_INSERT_HEAD(head, bp, hq);
-		CIRCLEQ_REMOVE(&mp->lqh, bp, q);
-		CIRCLEQ_INSERT_TAIL(&mp->lqh, bp, q);
+		TAILQ_REMOVE(head, bp, hq);
+		TAILQ_INSERT_HEAD(head, bp, hq);
+		TAILQ_REMOVE(&mp->lqh, bp, q);
+		TAILQ_INSERT_TAIL(&mp->lqh, bp, q);
 
 		/* Return a pinned page. */
 		bp->flags |= MPOOL_PINNED;
@@ -222,8 +222,8 @@ mpool_get(mp, pgno, flags)
 	 * of the lru chain.
 	 */
 	head = &mp->hqh[HASHKEY(bp->pgno)];
-	CIRCLEQ_INSERT_HEAD(head, bp, hq);
-	CIRCLEQ_INSERT_TAIL(&mp->lqh, bp, q);
+	TAILQ_INSERT_HEAD(head, bp, hq);
+	TAILQ_INSERT_TAIL(&mp->lqh, bp, q);
 
 	/* Run through the user's filter. */
 	if (mp->pgin != NULL)
@@ -271,8 +271,8 @@ mpool_close(mp)
 	BKT *bp;
 
 	/* Free up any space allocated to the lru pages. */
-	while ((bp = mp->lqh.cqh_first) != (void *)&mp->lqh) {
-		CIRCLEQ_REMOVE(&mp->lqh, mp->lqh.cqh_first, q);
+	while ((bp = TAILQ_FIRST(&mp->lqh)) != (void *)&mp->lqh) {
+		TAILQ_REMOVE(&mp->lqh, bp, q);
 		free(bp);
 	}
 
@@ -292,8 +292,7 @@ mpool_sync(mp)
 	BKT *bp;
 
 	/* Walk the lru chain, flushing any dirty pages to disk. */
-	for (bp = mp->lqh.cqh_first;
-	    bp != (void *)&mp->lqh; bp = bp->q.cqe_next)
+	TAILQ_FOREACH(bp, &mp->lqh, q)
 		if (bp->flags & MPOOL_DIRTY &&
 		    mpool_write(mp, bp) == RET_ERROR)
 			return (RET_ERROR);
@@ -323,8 +322,7 @@ mpool_bkt(mp)
 	 * off any lists.  If we don't find anything we grow the cache anyway.
 	 * The cache never shrinks.
 	 */
-	for (bp = mp->lqh.cqh_first;
-	    bp != (void *)&mp->lqh; bp = bp->q.cqe_next)
+	TAILQ_FOREACH(bp, &mp->lqh, q)
 		if (!(bp->flags & MPOOL_PINNED)) {
 			/* Flush if dirty. */
 			if (bp->flags & MPOOL_DIRTY &&
@@ -335,8 +333,8 @@ mpool_bkt(mp)
 #endif
 			/* Remove from the hash and lru queues. */
 			head = &mp->hqh[HASHKEY(bp->pgno)];
-			CIRCLEQ_REMOVE(head, bp, hq);
-			CIRCLEQ_REMOVE(&mp->lqh, bp, q);
+			TAILQ_REMOVE(head, bp, hq);
+			TAILQ_REMOVE(&mp->lqh, bp, q);
 #ifdef DEBUG
 			{ void *spage;
 				spage = bp->page;
@@ -402,7 +400,7 @@ mpool_look(mp, pgno)
 	BKT *bp;
 
 	head = &mp->hqh[HASHKEY(pgno)];
-	for (bp = head->cqh_first; bp != (void *)head; bp = bp->hq.cqe_next)
+	TAILQ_FOREACH(bp, head, hq)
 		if (bp->pgno == pgno) {
 #ifdef STATISTICS
 			++mp->cachehit;
@@ -446,8 +444,7 @@ mpool_stat(mp)
 
 	sep = "";
 	cnt = 0;
-	for (bp = mp->lqh.cqh_first;
-	    bp != (void *)&mp->lqh; bp = bp->q.cqe_next) {
+	TAILQ_FOREACH(bp, &mp->lqh, q) {
 		(void)fprintf(stderr, "%s%d", sep, bp->pgno);
 		if (bp->flags & MPOOL_DIRTY)
 			(void)fprintf(stderr, "d");