Btrfs: make metadata chunks smaller

This patch makes us a bit less zealous about making sure we have enough free
metadata space by pearing down the size of new metadata chunks to 256mb instead
of 1gb.  Also, we used to try an allocate metadata chunks when allocating data,
but that sort of thing is done elsewhere now so we can just remove it.  With my
-ENOSPC test I used to have 3gb reserved for metadata out of 75gb, now I have
1.7gb.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 39761ca07f15432ddaef1cb50bff740c7c877120..56e50137d0e6d066266c074b1e07e10d10cb1b5f 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4593,7 +4593,6 @@ int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
 {
        int ret;
        u64 search_start = 0;
-       struct btrfs_fs_info *info = root->fs_info;
 
        data = btrfs_get_alloc_profile(root, data);
 again:
@@ -4601,17 +4600,9 @@ again:
         * the only place that sets empty_size is btrfs_realloc_node, which
         * is not called recursively on allocations
         */
-       if (empty_size || root->ref_cows) {
-               if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
-                       ret = do_chunk_alloc(trans, root->fs_info->extent_root,
-                                    2 * 1024 * 1024,
-                                    BTRFS_BLOCK_GROUP_METADATA |
-                                    (info->metadata_alloc_profile &
-                                     info->avail_metadata_alloc_bits), 0);
-               }
+       if (empty_size || root->ref_cows)
                ret = do_chunk_alloc(trans, root->fs_info->extent_root,
                                     num_bytes + 2 * 1024 * 1024, data, 0);
-       }
 
        WARN_ON(num_bytes < root->sectorsize);
        ret = find_free_extent(trans, root, num_bytes, empty_size,

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 7eda483d7b5aa0cd5e5bd96d149cca6fe2fc8f16..198cff28766d494f3a919673775fe679d560722f 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2209,7 +2209,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
                max_chunk_size = 10 * calc_size;
                min_stripe_size = 64 * 1024 * 1024;
        } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
-               max_chunk_size = 4 * calc_size;
+               max_chunk_size = 256 * 1024 * 1024;
                min_stripe_size = 32 * 1024 * 1024;
        } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
                calc_size = 8 * 1024 * 1024;