diff --git a/fs/bcachefs/btree_write_buffer.c b/fs/bcachefs/btree_write_buffer.c
index 619d8c770d2ca..5e1262a542933 100644
--- a/fs/bcachefs/btree_write_buffer.c
+++ b/fs/bcachefs/btree_write_buffer.c
@@ -573,6 +573,29 @@ static void bch2_btree_write_buffer_flush_work(struct work_struct *work)
 	bch2_write_ref_put(c, BCH_WRITE_REF_btree_write_buffer);
 }
 
+static void wb_accounting_sort(struct btree_write_buffer *wb)
+{
+	eytzinger0_sort(wb->accounting.data, wb->accounting.nr,
+			sizeof(wb->accounting.data[0]),
+			wb_key_cmp, NULL);
+}
+
+int bch2_accounting_key_to_wb_slowpath(struct bch_fs *c, enum btree_id btree,
+				       struct bkey_i_accounting *k)
+{
+	struct btree_write_buffer *wb = &c->btree_write_buffer;
+	struct btree_write_buffered_key new = { .btree = btree };
+
+	bkey_copy(&new.k, &k->k_i);
+
+	int ret = darray_push(&wb->accounting, new);
+	if (ret)
+		return ret;
+
+	wb_accounting_sort(wb);
+	return 0;
+}
+
 int bch2_journal_key_to_wb_slowpath(struct bch_fs *c,
 			     struct journal_keys_to_wb *dst,
 			     enum btree_id btree, struct bkey_i *k)
@@ -642,11 +665,35 @@ void bch2_journal_keys_to_write_buffer_start(struct bch_fs *c, struct journal_ke
 
 	bch2_journal_pin_add(&c->journal, seq, &dst->wb->pin,
 			     bch2_btree_write_buffer_journal_flush);
+
+	darray_for_each(wb->accounting, i)
+		memset(&i->k.v, 0, bkey_val_bytes(&i->k.k));
 }
 
-void bch2_journal_keys_to_write_buffer_end(struct bch_fs *c, struct journal_keys_to_wb *dst)
+int bch2_journal_keys_to_write_buffer_end(struct bch_fs *c, struct journal_keys_to_wb *dst)
 {
 	struct btree_write_buffer *wb = &c->btree_write_buffer;
+	unsigned live_accounting_keys = 0;
+	int ret = 0;
+
+	darray_for_each(wb->accounting, i)
+		if (!bch2_accounting_key_is_zero(bkey_i_to_s_c_accounting(&i->k))) {
+			i->journal_seq = dst->seq;
+			live_accounting_keys++;
+			ret = __bch2_journal_key_to_wb(c, dst, i->btree, &i->k);
+			if (ret)
+				break;
+		}
+
+	if (live_accounting_keys * 2 < wb->accounting.nr) {
+		struct btree_write_buffered_key *dst = wb->accounting.data;
+
+		darray_for_each(wb->accounting, src)
+			if (!bch2_accounting_key_is_zero(bkey_i_to_s_c_accounting(&src->k)))
+				*dst++ = *src;
+		wb->accounting.nr = dst - wb->accounting.data;
+		wb_accounting_sort(wb);
+	}
 
 	if (!dst->wb->keys.nr)
 		bch2_journal_pin_drop(&c->journal, &dst->wb->pin);
@@ -659,6 +706,8 @@ void bch2_journal_keys_to_write_buffer_end(struct bch_fs *c, struct journal_keys
 	if (dst->wb == &wb->flushing)
 		mutex_unlock(&wb->flushing.lock);
 	mutex_unlock(&wb->inc.lock);
+
+	return ret;
 }
 
 static int bch2_journal_keys_to_write_buffer(struct bch_fs *c, struct journal_buf *buf)
@@ -682,7 +731,7 @@ static int bch2_journal_keys_to_write_buffer(struct bch_fs *c, struct journal_bu
 	buf->need_flush_to_write_buffer = false;
 	spin_unlock(&c->journal.lock);
 out:
-	bch2_journal_keys_to_write_buffer_end(c, &dst);
+	ret = bch2_journal_keys_to_write_buffer_end(c, &dst) ?: ret;
 	return ret;
 }
 
@@ -714,6 +763,7 @@ void bch2_fs_btree_write_buffer_exit(struct bch_fs *c)
 	BUG_ON((wb->inc.keys.nr || wb->flushing.keys.nr) &&
 	       !bch2_journal_error(&c->journal));
 
+	darray_exit(&wb->accounting);
 	darray_exit(&wb->sorted);
 	darray_exit(&wb->flushing.keys);
 	darray_exit(&wb->inc.keys);
diff --git a/fs/bcachefs/btree_write_buffer.h b/fs/bcachefs/btree_write_buffer.h
index eebcd2b15249a..ee3710eafeac3 100644
--- a/fs/bcachefs/btree_write_buffer.h
+++ b/fs/bcachefs/btree_write_buffer.h
@@ -3,6 +3,7 @@
 #define _BCACHEFS_BTREE_WRITE_BUFFER_H
 
 #include "bkey.h"
+#include "disk_accounting.h"
 
 static inline bool bch2_btree_write_buffer_should_flush(struct bch_fs *c)
 {
@@ -29,16 +30,45 @@ struct journal_keys_to_wb {
 	u64				seq;
 };
 
+static inline int wb_key_cmp(const void *_l, const void *_r)
+{
+	const struct btree_write_buffered_key *l = _l;
+	const struct btree_write_buffered_key *r = _r;
+
+	return cmp_int(l->btree, r->btree) ?: bpos_cmp(l->k.k.p, r->k.k.p);
+}
+
+int bch2_accounting_key_to_wb_slowpath(struct bch_fs *,
+			      enum btree_id, struct bkey_i_accounting *);
+
+static inline int bch2_accounting_key_to_wb(struct bch_fs *c,
+			     enum btree_id btree, struct bkey_i_accounting *k)
+{
+	struct btree_write_buffer *wb = &c->btree_write_buffer;
+	struct btree_write_buffered_key search;
+	search.btree = btree;
+	search.k.k.p = k->k.p;
+
+	unsigned idx = eytzinger0_find(wb->accounting.data, wb->accounting.nr,
+			sizeof(wb->accounting.data[0]),
+			wb_key_cmp, &search);
+
+	if (idx >= wb->accounting.nr)
+		return bch2_accounting_key_to_wb_slowpath(c, btree, k);
+
+	struct bkey_i_accounting *dst = bkey_i_to_accounting(&wb->accounting.data[idx].k);
+	bch2_accounting_accumulate(dst, accounting_i_to_s_c(k));
+	return 0;
+}
+
 int bch2_journal_key_to_wb_slowpath(struct bch_fs *,
 			     struct journal_keys_to_wb *,
 			     enum btree_id, struct bkey_i *);
 
-static inline int bch2_journal_key_to_wb(struct bch_fs *c,
+static inline int __bch2_journal_key_to_wb(struct bch_fs *c,
 			     struct journal_keys_to_wb *dst,
 			     enum btree_id btree, struct bkey_i *k)
 {
-	EBUG_ON(!dst->seq);
-
 	if (unlikely(!dst->room))
 		return bch2_journal_key_to_wb_slowpath(c, dst, btree, k);
 
@@ -51,8 +81,19 @@ static inline int bch2_journal_key_to_wb(struct bch_fs *c,
 	return 0;
 }
 
+static inline int bch2_journal_key_to_wb(struct bch_fs *c,
+			     struct journal_keys_to_wb *dst,
+			     enum btree_id btree, struct bkey_i *k)
+{
+	EBUG_ON(!dst->seq);
+
+	return k->k.type == KEY_TYPE_accounting
+		? bch2_accounting_key_to_wb(c, btree, bkey_i_to_accounting(k))
+		: __bch2_journal_key_to_wb(c, dst, btree, k);
+}
+
 void bch2_journal_keys_to_write_buffer_start(struct bch_fs *, struct journal_keys_to_wb *, u64);
-void bch2_journal_keys_to_write_buffer_end(struct bch_fs *, struct journal_keys_to_wb *);
+int bch2_journal_keys_to_write_buffer_end(struct bch_fs *, struct journal_keys_to_wb *);
 
 int bch2_btree_write_buffer_resize(struct bch_fs *, size_t);
 void bch2_fs_btree_write_buffer_exit(struct bch_fs *);
diff --git a/fs/bcachefs/btree_write_buffer_types.h b/fs/bcachefs/btree_write_buffer_types.h
index 9b9433de9c368..e9e76e20f43b0 100644
--- a/fs/bcachefs/btree_write_buffer_types.h
+++ b/fs/bcachefs/btree_write_buffer_types.h
@@ -52,6 +52,8 @@ struct btree_write_buffer {
 	struct btree_write_buffer_keys	inc;
 	struct btree_write_buffer_keys	flushing;
 	struct work_struct		flush_work;
+
+	DARRAY(struct btree_write_buffered_key) accounting;
 };
 
 #endif /* _BCACHEFS_BTREE_WRITE_BUFFER_TYPES_H */
diff --git a/fs/bcachefs/journal_io.c b/fs/bcachefs/journal_io.c
index 4b2ced9a48a49..5fda9a931babb 100644
--- a/fs/bcachefs/journal_io.c
+++ b/fs/bcachefs/journal_io.c
@@ -1848,8 +1848,14 @@ static int bch2_journal_write_prep(struct journal *j, struct journal_buf *w)
 		}
 	}
 
-	if (wb.wb)
-		bch2_journal_keys_to_write_buffer_end(c, &wb);
+	if (wb.wb) {
+		ret = bch2_journal_keys_to_write_buffer_end(c, &wb);
+		if (ret) {
+			bch2_fs_fatal_error(c, "error flushing journal keys to btree write buffer: %s",
+					    bch2_err_str(ret));
+			return ret;
+		}
+	}
 
 	spin_lock(&c->journal.lock);
 	w->need_flush_to_write_buffer = false;