search for: should_alloc_chunk

Josef''s fs_mark test fs_mark -d /mnt/btrfs-test -D 512 -t 16 -n 4096 -F -S0 on a 2GB single metadata fs leaves about 400Mb of metadata almost unused. This patch reduces metadata chunk allocations by considering the proper metadata chunk size of 200MB in should_alloc_chunk(), not the default 256MB which is set in __btrfs_alloc_chunk(). Signed-off-by: Itaru Kitayama <kitayama@cl.bb4.ne.jp> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 8c26441..54ab490 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -3241,6 +3241,8 @@ s...

...vation we drop bytes_may_use and add to bytes_reserved. We didn''t use to do this because delalloc would update bytes_may_use when it cleared delalloc. So now we don''t do this, we only will update bytes_may_use if we have an error and have to clear the accounting manually. 2) In should_alloc_chunk() we need to take into account the global_rsv size since that is basically used space. This will make sure we do actually alloc chunks. This logic needs to be reworked anyway, but since this is all very touchy I''ll leave that for a different patch. This passes Arne''s enospc tes...

...vation we drop bytes_may_use and add to bytes_reserved. We didn''t use to do this because delalloc would update bytes_may_use when it cleared delalloc. So now we don''t do this, we only will update bytes_may_use if we have an error and have to clear the accounting manually. 2) In should_alloc_chunk() we need to take into account the global_rsv size since that is basically used space. This will make sure we do actually alloc chunks. This logic needs to be reworked anyway, but since this is all very touchy I''ll leave that for a different patch. This passes Arne''s enospc tes...

...t-tree.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 50 insertions(+), 0 deletions(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 37e0a80..3bd5410 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -3396,6 +3396,50 @@ static int should_alloc_chunk(struct btrfs_root *root, return 1; } +static u64 get_system_chunk_thresh(struct btrfs_root *root, u64 type) +{ + u64 num_dev; + + if (type & BTRFS_BLOCK_GROUP_RAID10 || + type & BTRFS_BLOCK_GROUP_RAID0) + num_dev = root->fs_info->fs_devices->rw_devices; + else if (type &a...