diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2009-03-12 12:18:34 -0400 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2009-03-12 12:18:34 -0400 |
| commit | a4912123b688e057084e6557cef8924f7ae5bbde (patch) | |
| tree | 34e88705d6617b52caa0f87692b480119a9c9e2e /fs/ext4/mballoc.c | |
| parent | 2dc6b0d48ca0599837df21b14bb8393d0804af57 (diff) | |
ext4: New inode/block allocation algorithms for flex_bg filesystems
The find_group_flex() inode allocator is now only used if the
filesystem is mounted using the "oldalloc" mount option. It is
replaced with the original Orlov allocator that has been updated for
flex_bg filesystems (it should behave the same way if flex_bg is
disabled). The inode allocator now functions by taking into account
each flex_bg group, instead of each block group, when deciding whether
or not it's time to allocate a new directory into a fresh flex_bg.
The block allocator has also been changed so that the first block
group in each flex_bg is preferred for use for storing directory
blocks. This keeps directory blocks close together, which is good for
speeding up e2fsck since large directories are more likely to look
like this:
debugfs: stat /home/tytso/Maildir/cur
Inode: 1844562 Type: directory Mode: 0700 Flags: 0x81000
Generation: 1132745781 Version: 0x00000000:0000ad71
User: 15806 Group: 15806 Size: 1060864
File ACL: 0 Directory ACL: 0
Links: 2 Blockcount: 2072
Fragment: Address: 0 Number: 0 Size: 0
ctime: 0x499c0ff4:164961f4 -- Wed Feb 18 08:41:08 2009
atime: 0x499c0ff4:00000000 -- Wed Feb 18 08:41:08 2009
mtime: 0x49957f51:00000000 -- Fri Feb 13 09:10:25 2009
crtime: 0x499c0f57:00d51440 -- Wed Feb 18 08:38:31 2009
Size of extra inode fields: 28
BLOCKS:
(0):7348651, (1-258):7348654-7348911
TOTAL: 259
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/mballoc.c')
| -rw-r--r-- | fs/ext4/mballoc.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index b038188bd03..b0d6022eaa6 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -1726,6 +1726,7 @@ static int ext4_mb_good_group(struct ext4_allocation_context *ac, { unsigned free, fragments; unsigned i, bits; + int flex_size = ext4_flex_bg_size(EXT4_SB(ac->ac_sb)); struct ext4_group_desc *desc; struct ext4_group_info *grp = ext4_get_group_info(ac->ac_sb, group); @@ -1747,6 +1748,12 @@ static int ext4_mb_good_group(struct ext4_allocation_context *ac, if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) return 0; + /* Avoid using the first bg of a flexgroup for data files */ + if ((ac->ac_flags & EXT4_MB_HINT_DATA) && + (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) && + ((group % flex_size) == 0)) + return 0; + bits = ac->ac_sb->s_blocksize_bits + 1; for (i = ac->ac_2order; i <= bits; i++) if (grp->bb_counters[i] > 0) |