diff --git a/.bcachefs_revision b/.bcachefs_revision
index fba12e90..573681c5 100644
--- a/.bcachefs_revision
+++ b/.bcachefs_revision
@@ -1 +1 @@
-d763e8ab17ff1f5bdd9c5474ac15eb8791d31582
+3cd63315a62c8e2da15aa9fd59fa74ef40c9dc14
diff --git a/libbcachefs/bcachefs_format.h b/libbcachefs/bcachefs_format.h
index f6141fde..3b5e70a7 100644
--- a/libbcachefs/bcachefs_format.h
+++ b/libbcachefs/bcachefs_format.h
@@ -1294,7 +1294,8 @@ LE64_BITMASK(BCH_SB_ERASURE_CODE,	struct bch_sb, flags[3],  0, 16);
 	x(reflink,			6)	\
 	x(new_siphash,			7)	\
 	x(inline_data,			8)	\
-	x(new_extent_overwrite,		9)
+	x(new_extent_overwrite,		9)	\
+	x(incompressible,		10)
 
 enum bch_sb_feature {
 #define x(f, n) BCH_FEATURE_##f,
@@ -1374,11 +1375,12 @@ enum bch_csum_opts {
 };
 
 #define BCH_COMPRESSION_TYPES()		\
-	x(none,		0)		\
-	x(lz4_old,	1)		\
-	x(gzip,		2)		\
-	x(lz4,		3)		\
-	x(zstd,		4)
+	x(none,			0)	\
+	x(lz4_old,		1)	\
+	x(gzip,			2)	\
+	x(lz4,			3)	\
+	x(zstd,			4)	\
+	x(incompressible,	5)
 
 enum bch_compression_type {
 #define x(t, n) BCH_COMPRESSION_TYPE_##t,
diff --git a/libbcachefs/bkey_sort.c b/libbcachefs/bkey_sort.c
index 18f84201..7cbb5704 100644
--- a/libbcachefs/bkey_sort.c
+++ b/libbcachefs/bkey_sort.c
@@ -210,28 +210,38 @@ bch2_sort_repack_merge(struct bch_fs *c,
 		       bool filter_whiteouts)
 {
 	struct bkey_packed *prev = NULL, *k_packed;
-	struct bkey_s k;
+	struct bkey_on_stack k;
 	struct btree_nr_keys nr;
-	struct bkey unpacked;
 
 	memset(&nr, 0, sizeof(nr));
+	bkey_on_stack_init(&k);
 
 	while ((k_packed = bch2_btree_node_iter_next_all(iter, src))) {
 		if (filter_whiteouts && bkey_whiteout(k_packed))
 			continue;
 
-		k = __bkey_disassemble(src, k_packed, &unpacked);
+		/*
+		 * NOTE:
+		 * bch2_bkey_normalize may modify the key we pass it (dropping
+		 * stale pointers) and we don't have a write lock on the src
+		 * node; we have to make a copy of the entire key before calling
+		 * normalize
+		 */
+		bkey_on_stack_realloc(&k, c, k_packed->u64s + BKEY_U64s);
+		bch2_bkey_unpack(src, k.k, k_packed);
 
 		if (filter_whiteouts &&
-		    bch2_bkey_normalize(c, k))
+		    bch2_bkey_normalize(c, bkey_i_to_s(k.k)))
 			continue;
 
-		extent_sort_append(c, out_f, &nr, vstruct_last(dst), &prev, k);
+		extent_sort_append(c, out_f, &nr, vstruct_last(dst),
+				   &prev, bkey_i_to_s(k.k));
 	}
 
 	extent_sort_advance_prev(out_f, &nr, vstruct_last(dst), &prev);
 
 	dst->u64s = cpu_to_le16((u64 *) prev - dst->_data);
+	bkey_on_stack_exit(&k, c);
 	return nr;
 }
 
@@ -254,23 +264,18 @@ unsigned bch2_sort_keys(struct bkey_packed *dst,
 	sort_iter_sort(iter, sort_keys_cmp);
 
 	while ((in = sort_iter_next(iter, sort_keys_cmp))) {
+		bool needs_whiteout = false;
+
 		if (bkey_whiteout(in) &&
 		    (filter_whiteouts || !in->needs_whiteout))
 			continue;
 
-		if (bkey_whiteout(in) &&
-		    (next = sort_iter_peek(iter)) &&
-		    !bkey_cmp_packed(iter->b, in, next)) {
+		while ((next = sort_iter_peek(iter)) &&
+		       !bkey_cmp_packed(iter->b, in, next)) {
 			BUG_ON(in->needs_whiteout &&
 			       next->needs_whiteout);
-			/*
-			 * XXX racy, called with read lock from write path
-			 *
-			 * leads to spurious BUG_ON() in bkey_unpack_key() in
-			 * debug mode
-			 */
-			next->needs_whiteout |= in->needs_whiteout;
-			continue;
+			needs_whiteout |= in->needs_whiteout;
+			in = sort_iter_next(iter, sort_keys_cmp);
 		}
 
 		if (bkey_whiteout(in)) {
@@ -279,6 +284,7 @@ unsigned bch2_sort_keys(struct bkey_packed *dst,
 		} else {
 			bkey_copy(out, in);
 		}
+		out->needs_whiteout |= needs_whiteout;
 		out = bkey_next(out);
 	}
 
diff --git a/libbcachefs/bset.c b/libbcachefs/bset.c
index d6792d27..cf8fa59f 100644
--- a/libbcachefs/bset.c
+++ b/libbcachefs/bset.c
@@ -1397,21 +1397,21 @@ struct bkey_packed *bch2_bset_search_linear(struct btree *b,
 {
 	if (lossy_packed_search)
 		while (m != btree_bkey_last(b, t) &&
-		       bkey_iter_cmp_p_or_unp(b, search, lossy_packed_search,
-					      m) > 0)
+		       bkey_iter_cmp_p_or_unp(b, m,
+					lossy_packed_search, search) < 0)
 			m = bkey_next_skip_noops(m, btree_bkey_last(b, t));
 
 	if (!packed_search)
 		while (m != btree_bkey_last(b, t) &&
-		       bkey_iter_pos_cmp(b, search, m) > 0)
+		       bkey_iter_pos_cmp(b, m, search) < 0)
 			m = bkey_next_skip_noops(m, btree_bkey_last(b, t));
 
 	if (btree_keys_expensive_checks(b)) {
 		struct bkey_packed *prev = bch2_bkey_prev_all(b, t, m);
 
 		BUG_ON(prev &&
-		       bkey_iter_cmp_p_or_unp(b, search, packed_search,
-					      prev) <= 0);
+		       bkey_iter_cmp_p_or_unp(b, prev,
+					packed_search, search) >= 0);
 	}
 
 	return m;
diff --git a/libbcachefs/bset.h b/libbcachefs/bset.h
index 2653a74b..7338ccbc 100644
--- a/libbcachefs/bset.h
+++ b/libbcachefs/bset.h
@@ -199,12 +199,6 @@ __bkey_unpack_key_format_checked(const struct btree *b,
 		if (btree_keys_expensive_checks(b)) {
 			struct bkey dst2 = __bch2_bkey_unpack_key(&b->format, src);
 
-			/*
-			 * hack around a harmless race when compacting whiteouts
-			 * for a write:
-			 */
-			dst2.needs_whiteout = dst->needs_whiteout;
-
 			BUG_ON(memcmp(dst, &dst2, sizeof(*dst)));
 		}
 	}
@@ -360,7 +354,7 @@ void bch2_bset_delete(struct btree *, struct bkey_packed *, unsigned);
 static inline int bkey_cmp_p_or_unp(const struct btree *b,
 				    const struct bkey_packed *l,
 				    const struct bkey_packed *r_packed,
-				    struct bpos *r)
+				    const struct bpos *r)
 {
 	EBUG_ON(r_packed && !bkey_packed(r_packed));
 
@@ -449,7 +443,7 @@ static inline bool bch2_btree_node_iter_end(struct btree_node_iter *iter)
  * XXX: only need to compare pointers for keys that are both within a
  * btree_node_iterator - we need to break ties for prev() to work correctly
  */
-static inline int bkey_iter_cmp(struct btree *b,
+static inline int bkey_iter_cmp(const struct btree *b,
 				const struct bkey_packed *l,
 				const struct bkey_packed *r)
 {
@@ -458,7 +452,7 @@ static inline int bkey_iter_cmp(struct btree *b,
 		?: cmp_int(l, r);
 }
 
-static inline int btree_node_iter_cmp(struct btree *b,
+static inline int btree_node_iter_cmp(const struct btree *b,
 				      struct btree_node_iter_set l,
 				      struct btree_node_iter_set r)
 {
@@ -467,22 +461,22 @@ static inline int btree_node_iter_cmp(struct btree *b,
 			__btree_node_offset_to_key(b, r.k));
 }
 
-/* These assume l (the search key) is not a deleted key: */
-static inline int bkey_iter_pos_cmp(struct btree *b,
-			struct bpos *l,
-			const struct bkey_packed *r)
+/* These assume r (the search key) is not a deleted key: */
+static inline int bkey_iter_pos_cmp(const struct btree *b,
+			const struct bkey_packed *l,
+			const struct bpos *r)
 {
-	return -bkey_cmp_left_packed(b, r, l)
-		?: (int) bkey_deleted(r);
+	return bkey_cmp_left_packed(b, l, r)
+		?: -((int) bkey_deleted(l));
 }
 
-static inline int bkey_iter_cmp_p_or_unp(struct btree *b,
-			struct bpos *l,
-			const struct bkey_packed *l_packed,
-			const struct bkey_packed *r)
+static inline int bkey_iter_cmp_p_or_unp(const struct btree *b,
+				    const struct bkey_packed *l,
+				    const struct bkey_packed *r_packed,
+				    const struct bpos *r)
 {
-	return -bkey_cmp_p_or_unp(b, r, l_packed, l)
-		?: (int) bkey_deleted(r);
+	return bkey_cmp_p_or_unp(b, l, r_packed, r)
+		?: -((int) bkey_deleted(l));
 }
 
 static inline struct bkey_packed *
diff --git a/libbcachefs/btree_cache.h b/libbcachefs/btree_cache.h
index c5873c58..83358d6a 100644
--- a/libbcachefs/btree_cache.h
+++ b/libbcachefs/btree_cache.h
@@ -75,7 +75,7 @@ static inline unsigned btree_blocks(struct bch_fs *c)
 	return c->opts.btree_node_size >> c->block_bits;
 }
 
-#define BTREE_SPLIT_THRESHOLD(c)		(btree_blocks(c) * 3 / 4)
+#define BTREE_SPLIT_THRESHOLD(c)		(btree_max_u64s(c) * 3 / 4)
 
 #define BTREE_FOREGROUND_MERGE_THRESHOLD(c)	(btree_max_u64s(c) * 1 / 3)
 #define BTREE_FOREGROUND_MERGE_HYSTERESIS(c)			\
diff --git a/libbcachefs/btree_iter.c b/libbcachefs/btree_iter.c
index 988c550c..ea0555b8 100644
--- a/libbcachefs/btree_iter.c
+++ b/libbcachefs/btree_iter.c
@@ -11,10 +11,6 @@
 #include <linux/prefetch.h>
 #include <trace/events/bcachefs.h>
 
-static inline struct bkey_s_c __btree_iter_peek_all(struct btree_iter *,
-						    struct btree_iter_level *,
-						    struct bkey *);
-
 #define BTREE_ITER_NO_NODE_GET_LOCKS	((struct btree *) 1)
 #define BTREE_ITER_NO_NODE_DROP		((struct btree *) 2)
 #define BTREE_ITER_NO_NODE_LOCK_ROOT	((struct btree *) 3)
@@ -29,37 +25,14 @@ static inline bool is_btree_node(struct btree_iter *iter, unsigned l)
 		(unsigned long) iter->l[l].b >= 128;
 }
 
-/* Returns < 0 if @k is before iter pos, > 0 if @k is after */
-static inline int __btree_iter_pos_cmp(struct btree_iter *iter,
-				       const struct btree *b,
-				       const struct bkey_packed *k,
-				       bool interior_node)
+static inline struct bpos btree_iter_search_key(struct btree_iter *iter)
 {
-	int cmp = bkey_cmp_left_packed(b, k, &iter->pos);
+	struct bpos pos = iter->pos;
 
-	if (cmp)
-		return cmp;
-	if (bkey_deleted(k))
-		return -1;
-
-	/*
-	 * Normally, for extents we want the first key strictly greater than
-	 * the iterator position - with the exception that for interior nodes,
-	 * we don't want to advance past the last key if the iterator position
-	 * is POS_MAX:
-	 */
-	if (iter->flags & BTREE_ITER_IS_EXTENTS &&
-	    (!interior_node ||
-	     bkey_cmp_left_packed_byval(b, k, POS_MAX)))
-		return -1;
-	return 1;
-}
-
-static inline int btree_iter_pos_cmp(struct btree_iter *iter,
-				     const struct btree *b,
-				     const struct bkey_packed *k)
-{
-	return __btree_iter_pos_cmp(iter, b, k, b->level != 0);
+	if ((iter->flags & BTREE_ITER_IS_EXTENTS) &&
+	    bkey_cmp(pos, POS_MAX))
+		pos = bkey_successor(pos);
+	return pos;
 }
 
 /* Btree node locking: */
@@ -415,6 +388,7 @@ void bch2_trans_unlock(struct btree_trans *trans)
 static void __bch2_btree_iter_verify(struct btree_iter *iter,
 				     struct btree *b)
 {
+	struct bpos pos = btree_iter_search_key(iter);
 	struct btree_iter_level *l = &iter->l[b->level];
 	struct btree_node_iter tmp = l->iter;
 	struct bkey_packed *k;
@@ -437,17 +411,17 @@ static void __bch2_btree_iter_verify(struct btree_iter *iter,
 	k = b->level || iter->flags & BTREE_ITER_IS_EXTENTS
 		? bch2_btree_node_iter_prev_filter(&tmp, b, KEY_TYPE_discard)
 		: bch2_btree_node_iter_prev_all(&tmp, b);
-	if (k && btree_iter_pos_cmp(iter, b, k) > 0) {
+	if (k && bkey_iter_pos_cmp(b, k, &pos) >= 0) {
 		char buf[100];
 		struct bkey uk = bkey_unpack_key(b, k);
 
 		bch2_bkey_to_text(&PBUF(buf), &uk);
-		panic("prev key should be before iter pos:\n%s\n%llu:%llu\n",
+		panic("iterator should be before prev key:\n%s\n%llu:%llu\n",
 		      buf, iter->pos.inode, iter->pos.offset);
 	}
 
 	k = bch2_btree_node_iter_peek_all(&l->iter, b);
-	if (k && btree_iter_pos_cmp(iter, b, k) < 0) {
+	if (k && bkey_iter_pos_cmp(b, k, &pos) < 0) {
 		char buf[100];
 		struct bkey uk = bkey_unpack_key(b, k);
 
@@ -495,15 +469,19 @@ static void btree_node_iter_set_set_pos(struct btree_node_iter *iter,
 }
 
 static void __bch2_btree_iter_fix_key_modified(struct btree_iter *iter,
-						    struct btree *b,
-						    struct bkey_packed *where)
+					       struct btree *b,
+					       struct bkey_packed *where)
 {
-	struct btree_node_iter *node_iter = &iter->l[0].iter;
+	struct btree_iter_level *l = &iter->l[b->level];
+	struct bpos pos = btree_iter_search_key(iter);
 
-	if (where == bch2_btree_node_iter_peek_all(node_iter, b)) {
-		bkey_disassemble(b, where, &iter->k);
-		btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
-	}
+	if (where != bch2_btree_node_iter_peek_all(&l->iter, l->b))
+		return;
+
+	if (bkey_iter_pos_cmp(l->b, where, &pos) < 0)
+		bch2_btree_node_iter_advance(&l->iter, l->b);
+
+	btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
 }
 
 void bch2_btree_iter_fix_key_modified(struct btree_iter *iter,
@@ -535,6 +513,7 @@ static void __bch2_btree_node_iter_fix(struct btree_iter *iter,
 	bool iter_current_key_modified =
 		orig_iter_pos >= offset &&
 		orig_iter_pos <= offset + clobber_u64s;
+	struct bpos iter_pos = btree_iter_search_key(iter);
 
 	btree_node_iter_for_each(node_iter, set)
 		if (set->end == old_end)
@@ -542,7 +521,7 @@ static void __bch2_btree_node_iter_fix(struct btree_iter *iter,
 
 	/* didn't find the bset in the iterator - might have to readd it: */
 	if (new_u64s &&
-	    btree_iter_pos_cmp(iter, b, where) > 0) {
+	    bkey_iter_pos_cmp(b, where, &iter_pos) >= 0) {
 		bch2_btree_node_iter_push(node_iter, b, where, end);
 		goto fixup_done;
 	} else {
@@ -557,7 +536,7 @@ found:
 		return;
 
 	if (new_u64s &&
-	    btree_iter_pos_cmp(iter, b, where) > 0) {
+	    bkey_iter_pos_cmp(b, where, &iter_pos) >= 0) {
 		set->k = offset;
 	} else if (set->k < offset + clobber_u64s) {
 		set->k = offset + new_u64s;
@@ -702,11 +681,12 @@ static inline bool btree_iter_advance_to_pos(struct btree_iter *iter,
 					     struct btree_iter_level *l,
 					     int max_advance)
 {
+	struct bpos pos = btree_iter_search_key(iter);
 	struct bkey_packed *k;
 	int nr_advanced = 0;
 
 	while ((k = bch2_btree_node_iter_peek_all(&l->iter, l->b)) &&
-	       btree_iter_pos_cmp(iter, l->b, k) < 0) {
+	       bkey_iter_pos_cmp(l->b, k, &pos) < 0) {
 		if (max_advance > 0 && nr_advanced >= max_advance)
 			return false;
 
@@ -765,13 +745,7 @@ static inline bool btree_iter_pos_before_node(struct btree_iter *iter,
 static inline bool btree_iter_pos_after_node(struct btree_iter *iter,
 					     struct btree *b)
 {
-	int cmp = bkey_cmp(b->key.k.p, iter->pos);
-
-	if (!cmp &&
-	    (iter->flags & BTREE_ITER_IS_EXTENTS) &&
-	    bkey_cmp(b->key.k.p, POS_MAX))
-		cmp = -1;
-	return cmp < 0;
+	return bkey_cmp(b->key.k.p, btree_iter_search_key(iter)) < 0;
 }
 
 static inline bool btree_iter_pos_in_node(struct btree_iter *iter,
@@ -785,16 +759,10 @@ static inline bool btree_iter_pos_in_node(struct btree_iter *iter,
 static inline void __btree_iter_init(struct btree_iter *iter,
 				     unsigned level)
 {
+	struct bpos pos = btree_iter_search_key(iter);
 	struct btree_iter_level *l = &iter->l[level];
 
-	bch2_btree_node_iter_init(&l->iter, l->b, &iter->pos);
-
-	if (iter->flags & BTREE_ITER_IS_EXTENTS)
-		btree_iter_advance_to_pos(iter, l, -1);
-
-	/* Skip to first non whiteout: */
-	if (level)
-		bch2_btree_node_iter_peek(&l->iter, l->b);
+	bch2_btree_node_iter_init(&l->iter, l->b, &pos);
 
 	btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
 }
@@ -1371,12 +1339,6 @@ static inline struct bkey_s_c btree_iter_peek_uptodate(struct btree_iter *iter)
 		if (debug_check_iterators(iter->trans->c)) {
 			struct bkey k = bkey_unpack_key(l->b, _k);
 
-			/*
-			 * this flag is internal to the btree code,
-			 * we don't care if it doesn't match - if it's now set
-			 * it just means the key has been written out to disk:
-			 */
-			k.needs_whiteout = iter->k.needs_whiteout;
 			BUG_ON(memcmp(&k, &iter->k, sizeof(k)));
 		}
 
@@ -1564,9 +1526,7 @@ __bch2_btree_iter_peek_slot_extents(struct btree_iter *iter)
 	int ret;
 
 recheck:
-	while ((k = __btree_iter_peek_all(iter, l, &iter->k)).k &&
-	       bkey_cmp(k.k->p, iter->pos) <= 0)
-		bch2_btree_node_iter_advance(&l->iter, l->b);
+	btree_iter_advance_to_pos(iter, l, -1);
 
 	/*
 	 * iterator is now at the correct position for inserting at iter->pos,
@@ -1575,9 +1535,27 @@ recheck:
 	 */
 
 	node_iter = l->iter;
-	if (k.k && bkey_whiteout(k.k))
-		k = __btree_iter_unpack(iter, l, &iter->k,
-			bch2_btree_node_iter_peek(&node_iter, l->b));
+	k = __btree_iter_unpack(iter, l, &iter->k,
+		bch2_btree_node_iter_peek(&node_iter, l->b));
+
+	if (k.k && bkey_cmp(bkey_start_pos(k.k), iter->pos) <= 0) {
+		/*
+		 * If there wasn't actually a hole, want the iterator to be
+		 * pointed at the key we found:
+		 *
+		 * XXX: actually, we shouldn't be changing the iterator here:
+		 * the iterator needs to be correct for inserting at iter->pos,
+		 * and there may be whiteouts between iter->pos and what this
+		 * iterator points at:
+		 */
+		l->iter = node_iter;
+
+		EBUG_ON(bkey_cmp(k.k->p, iter->pos) <= 0);
+		iter->uptodate = BTREE_ITER_UPTODATE;
+
+		__bch2_btree_iter_verify(iter, l->b);
+		return k;
+	}
 
 	/*
 	 * If we got to the end of the node, check if we need to traverse to the
@@ -1592,24 +1570,6 @@ recheck:
 		goto recheck;
 	}
 
-	if (k.k &&
-	    !bkey_whiteout(k.k) &&
-	    bkey_cmp(bkey_start_pos(k.k), iter->pos) <= 0) {
-		/*
-		 * if we skipped forward to find the first non whiteout and
-		 * there _wasn't_ actually a hole, we want the iterator to be
-		 * pointed at the key we found:
-		 */
-		l->iter = node_iter;
-
-		EBUG_ON(bkey_cmp(k.k->p, iter->pos) < 0);
-		EBUG_ON(bkey_deleted(k.k));
-		iter->uptodate = BTREE_ITER_UPTODATE;
-
-		__bch2_btree_iter_verify(iter, l->b);
-		return k;
-	}
-
 	/* hole */
 
 	/* holes can't span inode numbers: */
diff --git a/libbcachefs/btree_types.h b/libbcachefs/btree_types.h
index 86e52468..b7af88e0 100644
--- a/libbcachefs/btree_types.h
+++ b/libbcachefs/btree_types.h
@@ -184,9 +184,25 @@ enum btree_iter_type {
 
 #define BTREE_ITER_TYPE			((1 << 2) - 1)
 
+/*
+ * Iterate over all possible positions, synthesizing deleted keys for holes:
+ */
 #define BTREE_ITER_SLOTS		(1 << 2)
+/*
+ * Indicates that intent locks should be taken on leaf nodes, because we expect
+ * to be doing updates:
+ */
 #define BTREE_ITER_INTENT		(1 << 3)
+/*
+ * Causes the btree iterator code to prefetch additional btree nodes from disk:
+ */
 #define BTREE_ITER_PREFETCH		(1 << 4)
+/*
+ * Indicates that this iterator should not be reused until transaction commit,
+ * either because a pending update references it or because the update depends
+ * on that particular key being locked (e.g. by the str_hash code, for hash
+ * table consistency)
+ */
 #define BTREE_ITER_KEEP_UNTIL_COMMIT	(1 << 5)
 /*
  * Used in bch2_btree_iter_traverse(), to indicate whether we're searching for
diff --git a/libbcachefs/btree_update_interior.c b/libbcachefs/btree_update_interior.c
index d84bb680..748e6356 100644
--- a/libbcachefs/btree_update_interior.c
+++ b/libbcachefs/btree_update_interior.c
@@ -1191,7 +1191,7 @@ static void bch2_insert_fixup_btree_ptr(struct btree_update *as, struct btree *b
 				     BTREE_TRIGGER_GC);
 
 	while ((k = bch2_btree_node_iter_peek_all(node_iter, b)) &&
-	       bkey_iter_pos_cmp(b, &insert->k.p, k) > 0)
+	       bkey_iter_pos_cmp(b, k, &insert->k.p) < 0)
 		bch2_btree_node_iter_advance(node_iter, b);
 
 	/*
@@ -1385,7 +1385,7 @@ static void btree_split(struct btree_update *as, struct btree *b,
 	if (keys)
 		btree_split_insert_keys(as, n1, iter, keys);
 
-	if (vstruct_blocks(n1->data, c->block_bits) > BTREE_SPLIT_THRESHOLD(c)) {
+	if (bset_u64s(&n1->set[0]) > BTREE_SPLIT_THRESHOLD(c)) {
 		trace_btree_split(c, b);
 
 		n2 = __btree_split_node(as, n1, iter);
diff --git a/libbcachefs/btree_update_leaf.c b/libbcachefs/btree_update_leaf.c
index dfbe5dcd..afd2086e 100644
--- a/libbcachefs/btree_update_leaf.c
+++ b/libbcachefs/btree_update_leaf.c
@@ -64,12 +64,45 @@ bool bch2_btree_bset_insert_key(struct btree_iter *iter,
 		bkey_cmp(insert->k.p, b->data->max_key) > 0);
 
 	k = bch2_btree_node_iter_peek_all(node_iter, b);
-	if (k && !bkey_cmp_packed(b, k, &insert->k)) {
-		BUG_ON(bkey_whiteout(k));
+	if (k && bkey_cmp_packed(b, k, &insert->k))
+		k = NULL;
 
+	/* @k is the key being overwritten/deleted, if any: */
+
+	EBUG_ON(k && bkey_whiteout(k));
+
+	if (bkey_whiteout(&insert->k)) {
+		/* Deleting: */
+
+		/* Not found? Nothing to do: */
+		if (!k)
+			return false;
+
+		btree_account_key_drop(b, k);
+		k->type = KEY_TYPE_deleted;
+
+		if (k->needs_whiteout) {
+			push_whiteout(iter->trans->c, b, k);
+			k->needs_whiteout = false;
+		}
+
+		if (k >= btree_bset_last(b)->start) {
+			clobber_u64s = k->u64s;
+
+			bch2_bset_delete(b, k, clobber_u64s);
+			bch2_btree_node_iter_fix(iter, b, node_iter, k,
+						 clobber_u64s, 0);
+		} else {
+			bch2_btree_iter_fix_key_modified(iter, b, k);
+		}
+
+		return true;
+	}
+
+	if (k) {
+		/* Overwriting: */
 		if (!bkey_written(b, k) &&
-		    bkey_val_u64s(&insert->k) == bkeyp_val_u64s(f, k) &&
-		    !bkey_whiteout(&insert->k)) {
+		    bkey_val_u64s(&insert->k) == bkeyp_val_u64s(f, k)) {
 			k->type = insert->k.type;
 			memcpy_u64s(bkeyp_val(f, k), &insert->v,
 				    bkey_val_u64s(&insert->k));
@@ -77,27 +110,7 @@ bool bch2_btree_bset_insert_key(struct btree_iter *iter,
 		}
 
 		btree_account_key_drop(b, k);
-
-		if (bkey_whiteout(&insert->k)) {
-			unsigned clobber_u64s = k->u64s, new_u64s = k->u64s;
-
-			k->type = KEY_TYPE_deleted;
-
-			if (k->needs_whiteout) {
-				push_whiteout(iter->trans->c, b, k);
-				k->needs_whiteout = false;
-			}
-
-			if (k >= btree_bset_last(b)->start) {
-				bch2_bset_delete(b, k, clobber_u64s);
-				new_u64s = 0;
-			}
-
-			bch2_btree_node_iter_fix(iter, b, node_iter, k,
-						 clobber_u64s, new_u64s);
-			return true;
-
-		}
+		k->type = KEY_TYPE_deleted;
 
 		insert->k.needs_whiteout = k->needs_whiteout;
 		k->needs_whiteout = false;
@@ -105,23 +118,9 @@ bool bch2_btree_bset_insert_key(struct btree_iter *iter,
 		if (k >= btree_bset_last(b)->start) {
 			clobber_u64s = k->u64s;
 			goto overwrite;
+		} else {
+			bch2_btree_iter_fix_key_modified(iter, b, k);
 		}
-
-		k->type = KEY_TYPE_deleted;
-		/*
-		 * XXX: we should be able to do this without two calls to
-		 * bch2_btree_node_iter_fix:
-		 */
-		bch2_btree_node_iter_fix(iter, b, node_iter, k,
-					 k->u64s, k->u64s);
-	} else {
-		/*
-		 * Deleting, but the key to delete wasn't found - nothing to do:
-		 */
-		if (bkey_whiteout(&insert->k))
-			return false;
-
-		insert->k.needs_whiteout = false;
 	}
 
 	k = bch2_btree_node_iter_bset_pos(node_iter, b, bset_tree_last(b));
@@ -707,10 +706,18 @@ int __bch2_trans_commit(struct btree_trans *trans)
 		trans_trigger_run = false;
 
 		trans_for_each_update(trans, i) {
-			/* we know trans->nounlock won't be set here: */
-			if (unlikely(!(i->iter->locks_want < 1
-				       ? __bch2_btree_iter_upgrade(i->iter, 1)
-				       : i->iter->uptodate <= BTREE_ITER_NEED_PEEK))) {
+			if (unlikely(i->iter->uptodate > BTREE_ITER_NEED_PEEK)) {
+				trace_trans_restart_traverse(trans->ip);
+				ret = -EINTR;
+				goto out;
+			}
+
+			/*
+			 * We're not using bch2_btree_iter_upgrade here because
+			 * we know trans->nounlock can't be set:
+			 */
+			if (unlikely(i->iter->locks_want < 1 &&
+				     !__bch2_btree_iter_upgrade(i->iter, 1))) {
 				trace_trans_restart_upgrade(trans->ip);
 				ret = -EINTR;
 				goto out;
diff --git a/libbcachefs/checksum.c b/libbcachefs/checksum.c
index a5c947e8..6f1afa4a 100644
--- a/libbcachefs/checksum.c
+++ b/libbcachefs/checksum.c
@@ -325,7 +325,7 @@ int bch2_rechecksum_bio(struct bch_fs *c, struct bio *bio,
 
 	BUG_ON(len_a + len_b > bio_sectors(bio));
 	BUG_ON(crc_old.uncompressed_size != bio_sectors(bio));
-	BUG_ON(crc_old.compression_type);
+	BUG_ON(crc_is_compressed(crc_old));
 	BUG_ON(bch2_csum_type_is_encryption(crc_old.csum_type) !=
 	       bch2_csum_type_is_encryption(new_csum_type));
 
@@ -354,6 +354,7 @@ int bch2_rechecksum_bio(struct bch_fs *c, struct bio *bio,
 		if (i->crc)
 			*i->crc = (struct bch_extent_crc_unpacked) {
 				.csum_type		= i->csum_type,
+				.compression_type	= crc_old.compression_type,
 				.compressed_size	= i->len,
 				.uncompressed_size	= i->len,
 				.offset			= 0,
diff --git a/libbcachefs/checksum.h b/libbcachefs/checksum.h
index ca9e4590..24dee803 100644
--- a/libbcachefs/checksum.h
+++ b/libbcachefs/checksum.h
@@ -155,13 +155,16 @@ static inline struct nonce null_nonce(void)
 static inline struct nonce extent_nonce(struct bversion version,
 					struct bch_extent_crc_unpacked crc)
 {
-	unsigned size = crc.compression_type ? crc.uncompressed_size : 0;
+	unsigned compression_type = crc_is_compressed(crc)
+		? crc.compression_type
+		: 0;
+	unsigned size = compression_type ? crc.uncompressed_size : 0;
 	struct nonce nonce = (struct nonce) {{
 		[0] = cpu_to_le32(size << 22),
 		[1] = cpu_to_le32(version.lo),
 		[2] = cpu_to_le32(version.lo >> 32),
 		[3] = cpu_to_le32(version.hi|
-				  (crc.compression_type << 24))^BCH_NONCE_EXTENT,
+				  (compression_type << 24))^BCH_NONCE_EXTENT,
 	}};
 
 	return nonce_add(nonce, crc.nonce << 9);
diff --git a/libbcachefs/compress.c b/libbcachefs/compress.c
index bb557eda..0959bb86 100644
--- a/libbcachefs/compress.c
+++ b/libbcachefs/compress.c
@@ -434,7 +434,7 @@ out:
 	bio_unmap_or_unbounce(c, dst_data);
 	return compression_type;
 err:
-	compression_type = 0;
+	compression_type = BCH_COMPRESSION_TYPE_incompressible;
 	goto out;
 }
 
diff --git a/libbcachefs/extents.c b/libbcachefs/extents.c
index c4b0b9e1..a19b91f9 100644
--- a/libbcachefs/extents.c
+++ b/libbcachefs/extents.c
@@ -337,7 +337,7 @@ enum merge_result bch2_extent_merge(struct bch_fs *c,
 			if (!bch2_checksum_mergeable(crc_l.csum_type))
 				return BCH_MERGE_NOMERGE;
 
-			if (crc_l.compression_type)
+			if (crc_is_compressed(crc_l))
 				return BCH_MERGE_NOMERGE;
 
 			if (crc_l.csum_type &&
@@ -448,7 +448,7 @@ static inline bool bch2_crc_unpacked_cmp(struct bch_extent_crc_unpacked l,
 static inline bool can_narrow_crc(struct bch_extent_crc_unpacked u,
 				  struct bch_extent_crc_unpacked n)
 {
-	return !u.compression_type &&
+	return !crc_is_compressed(u) &&
 		u.csum_type &&
 		u.uncompressed_size > u.live_size &&
 		bch2_csum_type_is_encryption(u.csum_type) ==
@@ -492,7 +492,7 @@ bool bch2_bkey_narrow_crcs(struct bkey_i *k, struct bch_extent_crc_unpacked n)
 	/* Find a checksum entry that covers only live data: */
 	if (!n.csum_type) {
 		bkey_for_each_crc(&k->k, ptrs, u, i)
-			if (!u.compression_type &&
+			if (!crc_is_compressed(u) &&
 			    u.csum_type &&
 			    u.live_size == u.uncompressed_size) {
 				n = u;
@@ -501,7 +501,7 @@ bool bch2_bkey_narrow_crcs(struct bkey_i *k, struct bch_extent_crc_unpacked n)
 		return false;
 	}
 found:
-	BUG_ON(n.compression_type);
+	BUG_ON(crc_is_compressed(n));
 	BUG_ON(n.offset);
 	BUG_ON(n.live_size != k->k.size);
 
@@ -610,8 +610,7 @@ unsigned bch2_bkey_nr_ptrs_fully_allocated(struct bkey_s_c k)
 		struct extent_ptr_decoded p;
 
 		bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
-			ret += !p.ptr.cached &&
-				p.crc.compression_type == BCH_COMPRESSION_TYPE_none;
+			ret += !p.ptr.cached && !crc_is_compressed(p.crc);
 	}
 
 	return ret;
@@ -625,13 +624,24 @@ unsigned bch2_bkey_sectors_compressed(struct bkey_s_c k)
 	unsigned ret = 0;
 
 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
-		if (!p.ptr.cached &&
-		    p.crc.compression_type != BCH_COMPRESSION_TYPE_none)
+		if (!p.ptr.cached && crc_is_compressed(p.crc))
 			ret += p.crc.compressed_size;
 
 	return ret;
 }
 
+bool bch2_bkey_is_incompressible(struct bkey_s_c k)
+{
+	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+	const union bch_extent_entry *entry;
+	struct bch_extent_crc_unpacked crc;
+
+	bkey_for_each_crc(k.k, ptrs, crc, entry)
+		if (crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)
+			return true;
+	return false;
+}
+
 bool bch2_check_range_allocated(struct bch_fs *c, struct bpos pos, u64 size,
 				unsigned nr_replicas)
 {
diff --git a/libbcachefs/extents.h b/libbcachefs/extents.h
index 7c5a41e6..0d855417 100644
--- a/libbcachefs/extents.h
+++ b/libbcachefs/extents.h
@@ -175,6 +175,12 @@ bch2_extent_crc_unpack(const struct bkey *k, const union bch_extent_crc *crc)
 #undef common_fields
 }
 
+static inline bool crc_is_compressed(struct bch_extent_crc_unpacked crc)
+{
+	return (crc.compression_type != BCH_COMPRESSION_TYPE_none &&
+		crc.compression_type != BCH_COMPRESSION_TYPE_incompressible);
+}
+
 /* bkey_ptrs: generically over any key type that has ptrs */
 
 struct bkey_ptrs_c {
@@ -483,6 +489,7 @@ static inline struct bch_devs_list bch2_bkey_cached_devs(struct bkey_s_c k)
 unsigned bch2_bkey_nr_ptrs(struct bkey_s_c);
 unsigned bch2_bkey_nr_ptrs_allocated(struct bkey_s_c);
 unsigned bch2_bkey_nr_ptrs_fully_allocated(struct bkey_s_c);
+bool bch2_bkey_is_incompressible(struct bkey_s_c);
 unsigned bch2_bkey_sectors_compressed(struct bkey_s_c);
 bool bch2_check_range_allocated(struct bch_fs *, struct bpos, u64, unsigned);
 unsigned bch2_bkey_durability(struct bch_fs *, struct bkey_s_c);
diff --git a/libbcachefs/io.c b/libbcachefs/io.c
index 4c7dd099..ca83d79e 100644
--- a/libbcachefs/io.c
+++ b/libbcachefs/io.c
@@ -546,9 +546,14 @@ static void __bch2_write_index(struct bch_write_op *op)
 	 * particularly want to plumb io_opts all the way through the btree
 	 * update stack right now
 	 */
-	for_each_keylist_key(keys, k)
+	for_each_keylist_key(keys, k) {
 		bch2_rebalance_add_key(c, bkey_i_to_s_c(k), &op->opts);
 
+		if (bch2_bkey_is_incompressible(bkey_i_to_s_c(k)))
+			bch2_check_set_feature(op->c, BCH_FEATURE_incompressible);
+
+	}
+
 	if (!bch2_keylist_empty(keys)) {
 		u64 sectors_start = keylist_sectors(keys);
 		int ret = op->index_update_fn(op);
@@ -784,8 +789,9 @@ static enum prep_encoded_ret {
 	/* Can we just write the entire extent as is? */
 	if (op->crc.uncompressed_size == op->crc.live_size &&
 	    op->crc.compressed_size <= wp->sectors_free &&
-	    op->crc.compression_type == op->compression_type) {
-		if (!op->crc.compression_type &&
+	    (op->crc.compression_type == op->compression_type ||
+	     op->incompressible)) {
+		if (!crc_is_compressed(op->crc) &&
 		    op->csum_type != op->crc.csum_type &&
 		    bch2_write_rechecksum(c, op, op->csum_type))
 			return PREP_ENCODED_CHECKSUM_ERR;
@@ -797,7 +803,7 @@ static enum prep_encoded_ret {
 	 * If the data is compressed and we couldn't write the entire extent as
 	 * is, we have to decompress it:
 	 */
-	if (op->crc.compression_type) {
+	if (crc_is_compressed(op->crc)) {
 		struct bch_csum csum;
 
 		if (bch2_write_decrypt(op))
@@ -864,6 +870,7 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 		ret = -EIO;
 		goto err;
 	case PREP_ENCODED_CHECKSUM_ERR:
+		BUG();
 		goto csum_err;
 	case PREP_ENCODED_DO_WRITE:
 		/* XXX look for bug here */
@@ -908,11 +915,13 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 		       bch2_csum_type_is_encryption(op->crc.csum_type));
 		BUG_ON(op->compression_type && !bounce);
 
-		crc.compression_type = op->compression_type
-			?  bch2_bio_compress(c, dst, &dst_len, src, &src_len,
-					     op->compression_type)
+		crc.compression_type = op->incompressible
+			? BCH_COMPRESSION_TYPE_incompressible
+			: op->compression_type
+			? bch2_bio_compress(c, dst, &dst_len, src, &src_len,
+					    op->compression_type)
 			: 0;
-		if (!crc.compression_type) {
+		if (!crc_is_compressed(crc)) {
 			dst_len = min(dst->bi_iter.bi_size, src->bi_iter.bi_size);
 			dst_len = min_t(unsigned, dst_len, wp->sectors_free << 9);
 
@@ -941,7 +950,7 @@ static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 		}
 
 		if ((op->flags & BCH_WRITE_DATA_ENCODED) &&
-		    !crc.compression_type &&
+		    !crc_is_compressed(crc) &&
 		    bch2_csum_type_is_encryption(op->crc.csum_type) ==
 		    bch2_csum_type_is_encryption(op->csum_type)) {
 			/*
@@ -1338,6 +1347,7 @@ static void promote_start(struct promote_op *op, struct bch_read_bio *rbio)
 
 static struct promote_op *__promote_alloc(struct bch_fs *c,
 					  enum btree_id btree_id,
+					  struct bkey_s_c k,
 					  struct bpos pos,
 					  struct extent_ptr_decoded *pick,
 					  struct bch_io_opts opts,
@@ -1394,8 +1404,7 @@ static struct promote_op *__promote_alloc(struct bch_fs *c,
 			(struct data_opts) {
 				.target = opts.promote_target
 			},
-			btree_id,
-			bkey_s_c_null);
+			btree_id, k);
 	BUG_ON(ret);
 
 	return op;
@@ -1437,7 +1446,7 @@ static struct promote_op *promote_alloc(struct bch_fs *c,
 				  k.k->type == KEY_TYPE_reflink_v
 				  ? BTREE_ID_REFLINK
 				  : BTREE_ID_EXTENTS,
-				  pos, pick, opts, sectors, rbio);
+				  k, pos, pick, opts, sectors, rbio);
 	if (!promote)
 		return NULL;
 
@@ -1701,7 +1710,7 @@ static void bch2_rbio_narrow_crcs(struct bch_read_bio *rbio)
 	u64 data_offset = rbio->pos.offset - rbio->pick.crc.offset;
 	int ret;
 
-	if (rbio->pick.crc.compression_type)
+	if (crc_is_compressed(rbio->pick.crc))
 		return;
 
 	bkey_on_stack_init(&new);
@@ -1786,7 +1795,7 @@ static void __bch2_read_endio(struct work_struct *work)
 	crc.offset     += rbio->offset_into_extent;
 	crc.live_size	= bvec_iter_sectors(rbio->bvec_iter);
 
-	if (crc.compression_type != BCH_COMPRESSION_TYPE_none) {
+	if (crc_is_compressed(crc)) {
 		bch2_encrypt_bio(c, crc.csum_type, nonce, src);
 		if (bch2_bio_uncompress(c, src, dst, dst_iter, crc))
 			goto decompression_err;
@@ -1883,7 +1892,7 @@ static void bch2_read_endio(struct bio *bio)
 	}
 
 	if (rbio->narrow_crcs ||
-	    rbio->pick.crc.compression_type ||
+	    crc_is_compressed(rbio->pick.crc) ||
 	    bch2_csum_type_is_encryption(rbio->pick.crc.csum_type))
 		context = RBIO_CONTEXT_UNBOUND,	wq = system_unbound_wq;
 	else if (rbio->pick.crc.csum_type)
@@ -1994,7 +2003,7 @@ int __bch2_read_extent(struct bch_fs *c, struct bch_read_bio *orig,
 
 	EBUG_ON(offset_into_extent + bvec_iter_sectors(iter) > k.k->size);
 
-	if (pick.crc.compression_type != BCH_COMPRESSION_TYPE_none ||
+	if (crc_is_compressed(pick.crc) ||
 	    (pick.crc.csum_type != BCH_CSUM_NONE &&
 	     (bvec_iter_sectors(iter) != pick.crc.uncompressed_size ||
 	      (bch2_csum_type_is_encryption(pick.crc.csum_type) &&
@@ -2009,7 +2018,7 @@ int __bch2_read_extent(struct bch_fs *c, struct bch_read_bio *orig,
 					&rbio, &bounce, &read_full);
 
 	if (!read_full) {
-		EBUG_ON(pick.crc.compression_type);
+		EBUG_ON(crc_is_compressed(pick.crc));
 		EBUG_ON(pick.crc.csum_type &&
 			(bvec_iter_sectors(iter) != pick.crc.uncompressed_size ||
 			 bvec_iter_sectors(iter) != pick.crc.live_size ||
diff --git a/libbcachefs/io_types.h b/libbcachefs/io_types.h
index c37b7d74..7f7b69b3 100644
--- a/libbcachefs/io_types.h
+++ b/libbcachefs/io_types.h
@@ -105,6 +105,7 @@ struct bch_write_op {
 	unsigned		nr_replicas:4;
 	unsigned		nr_replicas_required:4;
 	unsigned		alloc_reserve:4;
+	unsigned		incompressible:1;
 
 	struct bch_devs_list	devs_have;
 	u16			target;
diff --git a/libbcachefs/move.c b/libbcachefs/move.c
index 257e00ae..ecc74ebe 100644
--- a/libbcachefs/move.c
+++ b/libbcachefs/move.c
@@ -215,6 +215,9 @@ int bch2_migrate_write_init(struct bch_fs *c, struct migrate_write *m,
 			    enum btree_id btree_id,
 			    struct bkey_s_c k)
 {
+	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+	const union bch_extent_entry *entry;
+	struct extent_ptr_decoded p;
 	int ret;
 
 	m->btree_id	= btree_id;
@@ -223,9 +226,14 @@ int bch2_migrate_write_init(struct bch_fs *c, struct migrate_write *m,
 	m->nr_ptrs_reserved = 0;
 
 	bch2_write_op_init(&m->op, c, io_opts);
-	m->op.compression_type =
-		bch2_compression_opt_to_type[io_opts.background_compression ?:
-					     io_opts.compression];
+
+	if (!bch2_bkey_is_incompressible(k))
+		m->op.compression_type =
+			bch2_compression_opt_to_type[io_opts.background_compression ?:
+						     io_opts.compression];
+	else
+		m->op.incompressible = true;
+
 	m->op.target	= data_opts.target,
 	m->op.write_point = wp;
 
@@ -265,14 +273,11 @@ int bch2_migrate_write_init(struct bch_fs *c, struct migrate_write *m,
 		break;
 	}
 	case DATA_REWRITE: {
-		struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
-		const union bch_extent_entry *entry;
-		struct extent_ptr_decoded p;
 		unsigned compressed_sectors = 0;
 
 		bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 			if (!p.ptr.cached &&
-			    p.crc.compression_type != BCH_COMPRESSION_TYPE_none &&
+			    crc_is_compressed(p.crc) &&
 			    bch2_dev_in_target(c, p.ptr.dev, data_opts.target))
 				compressed_sectors += p.crc.compressed_size;
 
diff --git a/libbcachefs/rebalance.c b/libbcachefs/rebalance.c
index 84b3fb6e..ab193432 100644
--- a/libbcachefs/rebalance.c
+++ b/libbcachefs/rebalance.c
@@ -17,50 +17,52 @@
 #include <linux/sched/cputime.h>
 #include <trace/events/bcachefs.h>
 
-static inline bool rebalance_ptr_pred(struct bch_fs *c,
-				      struct extent_ptr_decoded p,
-				      struct bch_io_opts *io_opts)
+/*
+ * Check if an extent should be moved:
+ * returns -1 if it should not be moved, or
+ * device of pointer that should be moved, if known, or INT_MAX if unknown
+ */
+static int __bch2_rebalance_pred(struct bch_fs *c,
+				 struct bkey_s_c k,
+				 struct bch_io_opts *io_opts)
 {
-	if (io_opts->background_target &&
-	    !bch2_dev_in_target(c, p.ptr.dev, io_opts->background_target) &&
-	    !p.ptr.cached)
-		return true;
+	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+	const union bch_extent_entry *entry;
+	struct extent_ptr_decoded p;
 
 	if (io_opts->background_compression &&
-	    p.crc.compression_type !=
-	    bch2_compression_opt_to_type[io_opts->background_compression])
-		return true;
+	    !bch2_bkey_is_incompressible(k))
+		bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
+			if (!p.ptr.cached &&
+			    p.crc.compression_type !=
+			    bch2_compression_opt_to_type[io_opts->background_compression])
+				return p.ptr.dev;
 
-	return false;
+	if (io_opts->background_target)
+		bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
+			if (!p.ptr.cached &&
+			    !bch2_dev_in_target(c, p.ptr.dev, io_opts->background_target))
+				return p.ptr.dev;
+
+	return -1;
 }
 
 void bch2_rebalance_add_key(struct bch_fs *c,
 			    struct bkey_s_c k,
 			    struct bch_io_opts *io_opts)
 {
-	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
-	const union bch_extent_entry *entry;
-	struct extent_ptr_decoded p;
+	atomic64_t *counter;
+	int dev;
 
-	if (!io_opts->background_target &&
-	    !io_opts->background_compression)
+	dev = __bch2_rebalance_pred(c, k, io_opts);
+	if (dev < 0)
 		return;
 
-	bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
-		if (rebalance_ptr_pred(c, p, io_opts)) {
-			struct bch_dev *ca = bch_dev_bkey_exists(c, p.ptr.dev);
+	counter = dev < INT_MAX
+		? &bch_dev_bkey_exists(c, dev)->rebalance_work
+		: &c->rebalance.work_unknown_dev;
 
-			if (atomic64_add_return(p.crc.compressed_size,
-						&ca->rebalance_work) ==
-			    p.crc.compressed_size)
-				rebalance_wakeup(c);
-		}
-}
-
-void bch2_rebalance_add_work(struct bch_fs *c, u64 sectors)
-{
-	if (atomic64_add_return(sectors, &c->rebalance.work_unknown_dev) ==
-	    sectors)
+	if (atomic64_add_return(k.k->size, counter) == k.k->size)
 		rebalance_wakeup(c);
 }
 
@@ -69,26 +71,20 @@ static enum data_cmd rebalance_pred(struct bch_fs *c, void *arg,
 				    struct bch_io_opts *io_opts,
 				    struct data_opts *data_opts)
 {
-	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
-	const union bch_extent_entry *entry;
-	struct extent_ptr_decoded p;
-	unsigned nr_replicas = 0;
-
-	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
-		nr_replicas += !p.ptr.cached;
-
-		if (rebalance_ptr_pred(c, p, io_opts))
-			goto found;
+	if (__bch2_rebalance_pred(c, k, io_opts) >= 0) {
+		data_opts->target		= io_opts->background_target;
+		data_opts->btree_insert_flags	= 0;
+		return DATA_ADD_REPLICAS;
+	} else {
+		return DATA_SKIP;
 	}
+}
 
-	if (nr_replicas < io_opts->data_replicas)
-		goto found;
-
-	return DATA_SKIP;
-found:
-	data_opts->target		= io_opts->background_target;
-	data_opts->btree_insert_flags	= 0;
-	return DATA_ADD_REPLICAS;
+void bch2_rebalance_add_work(struct bch_fs *c, u64 sectors)
+{
+	if (atomic64_add_return(sectors, &c->rebalance.work_unknown_dev) ==
+	    sectors)
+		rebalance_wakeup(c);
 }
 
 struct rebalance_work {
@@ -183,6 +179,8 @@ static int bch2_rebalance_thread(void *arg)
 	prev_cputime	= curr_cputime();
 
 	while (!kthread_wait_freezable(r->enabled)) {
+		cond_resched();
+
 		start			= jiffies;
 		cputime			= curr_cputime();
 
diff --git a/libbcachefs/sysfs.c b/libbcachefs/sysfs.c
index 602def1e..d78ffcc0 100644
--- a/libbcachefs/sysfs.c
+++ b/libbcachefs/sysfs.c
@@ -276,7 +276,7 @@ static ssize_t bch2_compression_stats(struct bch_fs *c, char *buf)
 			struct extent_ptr_decoded p;
 
 			extent_for_each_ptr_decode(e, p, entry) {
-				if (p.crc.compression_type == BCH_COMPRESSION_TYPE_none) {
+				if (!crc_is_compressed(p.crc)) {
 					nr_uncompressed_extents++;
 					uncompressed_sectors += e.k->size;
 				} else {