From 2dd3e67b1eaec8504da7e12b8afee77323a49f38 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Mon, 4 Aug 2008 08:20:15 -0400 Subject: [PATCH] Btrfs: More throttle tuning * Make walk_down_tree wake up throttled tasks more often * Make walk_down_tree call cond_resched during long loops * As the size of the ref cache grows, wait longer in throttle * Get rid of the reada code in walk_down_tree, the leaves don't get read anymore, thanks to the ref cache. Signed-off-by: Chris Mason --- fs/btrfs/disk-io.c | 13 ++-------- fs/btrfs/extent-tree.c | 59 +++++++++--------------------------------- fs/btrfs/transaction.c | 15 +++++++++++ 3 files changed, 29 insertions(+), 58 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index d2d1cc87e8ad..da9dda4338a3 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -188,13 +188,6 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf, btrfs_csum_final(crc, result); if (verify) { - int from_this_trans = 0; - - if (root->fs_info->running_transaction && - btrfs_header_generation(buf) == - root->fs_info->running_transaction->transid) - from_this_trans = 1; - /* FIXME, this is not good */ if (memcmp_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE)) { u32 val; @@ -203,11 +196,9 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf, read_extent_buffer(buf, &val, 0, BTRFS_CRC32_SIZE); printk("btrfs: %s checksum verify failed on %llu " - "wanted %X found %X from_this_trans %d " - "level %d\n", + "wanted %X found %X level %d\n", root->fs_info->sb->s_id, - buf->start, val, found, from_this_trans, - btrfs_header_level(buf)); + buf->start, val, found, btrfs_header_level(buf)); return 1; } } else { diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 98a1c0faedae..1aeb695078b9 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -2369,6 +2369,11 @@ static int noinline drop_leaf_ref_no_cache(struct btrfs_trans_handle *trans, leaf_owner, leaf_generation, key.objectid, key.offset, 0); mutex_unlock(&root->fs_info->alloc_mutex); + + atomic_inc(&root->fs_info->throttle_gen); + wake_up(&root->fs_info->transaction_throttle); + cond_resched(); + BUG_ON(ret); } return 0; @@ -2389,6 +2394,11 @@ static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans, ref->owner, ref->generation, info->objectid, info->offset, 0); mutex_unlock(&root->fs_info->alloc_mutex); + + atomic_inc(&root->fs_info->throttle_gen); + wake_up(&root->fs_info->transaction_throttle); + cond_resched(); + BUG_ON(ret); info++; } @@ -2396,51 +2406,6 @@ static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans, return 0; } -static void noinline reada_walk_down(struct btrfs_root *root, - struct extent_buffer *node, - int slot) -{ - u64 bytenr; - u64 last = 0; - u32 nritems; - u32 refs; - u32 blocksize; - int ret; - int i; - int level; - int skipped = 0; - - nritems = btrfs_header_nritems(node); - level = btrfs_header_level(node); - if (level) - return; - - for (i = slot; i < nritems && skipped < 32; i++) { - bytenr = btrfs_node_blockptr(node, i); - if (last && ((bytenr > last && bytenr - last > 32 * 1024) || - (last > bytenr && last - bytenr > 32 * 1024))) { - skipped++; - continue; - } - blocksize = btrfs_level_size(root, level - 1); - if (i != slot) { - ret = lookup_extent_ref(NULL, root, bytenr, - blocksize, &refs); - BUG_ON(ret); - if (refs != 1) { - skipped++; - continue; - } - } - ret = readahead_tree_block(root, bytenr, blocksize, - btrfs_node_ptr_generation(node, i)); - last = bytenr + blocksize; - cond_resched(); - if (ret) - break; - } -} - int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start, u64 len, u32 *refs) { @@ -2549,6 +2514,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans, atomic_inc(&root->fs_info->throttle_gen); wake_up(&root->fs_info->transaction_throttle); + cond_resched(); continue; } @@ -2578,8 +2544,6 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans, if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) { free_extent_buffer(next); - if (path->slots[*level] == 0) - reada_walk_down(root, cur, path->slots[*level]); next = read_tree_block(root, bytenr, blocksize, ptr_gen); cond_resched(); @@ -2601,6 +2565,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans, path->nodes[*level-1] = next; *level = btrfs_header_level(next); path->slots[*level] = 0; + cond_resched(); } out: WARN_ON(*level < 0); diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 9d84daf10008..cf73342e8215 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -210,7 +210,9 @@ static noinline int wait_for_commit(struct btrfs_root *root, static void throttle_on_drops(struct btrfs_root *root) { struct btrfs_fs_info *info = root->fs_info; + int harder_count = 0; +harder: if (atomic_read(&info->throttles)) { DEFINE_WAIT(wait); int thr; @@ -226,6 +228,19 @@ static void throttle_on_drops(struct btrfs_root *root) schedule(); finish_wait(&info->transaction_throttle, &wait); } while (thr == atomic_read(&info->throttle_gen)); + harder_count++; + + if (root->fs_info->total_ref_cache_size > 1 * 1024 * 1024 && + harder_count < 2) + goto harder; + + if (root->fs_info->total_ref_cache_size > 5 * 1024 * 1024 && + harder_count < 10) + goto harder; + + if (root->fs_info->total_ref_cache_size > 10 * 1024 * 1024 && + harder_count < 20) + goto harder; } } -- 2.20.1