linux/fs/bcachefs/btree_key_cache.h
Kent Overstreet 241e26369e bcachefs: Don't flush btree writes more aggressively because of btree key cache
We need to flush the btree key cache when it's too dirty, because
otherwise the shrinker won't be able to reclaim memory - this is done by
journal reclaim. But journal reclaim also kicks btree node writes: this
meant that btree node writes were getting kicked much too often just
because we needed to flush btree key cache keys.

This patch splits journal pins into two different lists, and teaches
journal reclaim to not flush btree node writes when it only needs to
flush key cache keys.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:59 -04:00

54 lines
1.8 KiB
C

#ifndef _BCACHEFS_BTREE_KEY_CACHE_H
#define _BCACHEFS_BTREE_KEY_CACHE_H
static inline size_t bch2_nr_btree_keys_need_flush(struct bch_fs *c)
{
size_t nr_dirty = atomic_long_read(&c->btree_key_cache.nr_dirty);
size_t nr_keys = atomic_long_read(&c->btree_key_cache.nr_keys);
size_t max_dirty = 1024 + nr_keys / 2;
return max_t(ssize_t, 0, nr_dirty - max_dirty);
}
static inline bool bch2_btree_key_cache_must_wait(struct bch_fs *c)
{
size_t nr_dirty = atomic_long_read(&c->btree_key_cache.nr_dirty);
size_t nr_keys = atomic_long_read(&c->btree_key_cache.nr_keys);
size_t max_dirty = 4096 + (nr_keys * 3) / 4;
return nr_dirty > max_dirty &&
test_bit(JOURNAL_RECLAIM_STARTED, &c->journal.flags);
}
int bch2_btree_key_cache_journal_flush(struct journal *,
struct journal_entry_pin *, u64);
struct bkey_cached *
bch2_btree_key_cache_find(struct bch_fs *, enum btree_id, struct bpos);
int bch2_btree_iter_traverse_cached(struct btree_iter *);
bool bch2_btree_insert_key_cached(struct btree_trans *,
struct btree_iter *, struct bkey_i *);
int bch2_btree_key_cache_flush(struct btree_trans *,
enum btree_id, struct bpos);
#ifdef CONFIG_BCACHEFS_DEBUG
void bch2_btree_key_cache_verify_clean(struct btree_trans *,
enum btree_id, struct bpos);
#else
static inline void
bch2_btree_key_cache_verify_clean(struct btree_trans *trans,
enum btree_id id, struct bpos pos) {}
#endif
void bch2_fs_btree_key_cache_exit(struct btree_key_cache *);
void bch2_fs_btree_key_cache_init_early(struct btree_key_cache *);
int bch2_fs_btree_key_cache_init(struct btree_key_cache *);
void bch2_btree_key_cache_to_text(struct printbuf *, struct btree_key_cache *);
void bch2_btree_key_cache_exit(void);
int __init bch2_btree_key_cache_init(void);
#endif /* _BCACHEFS_BTREE_KEY_CACHE_H */