On 2011-07-19, at 11:38 PM, hao.bigrat@gmail.com wrote:

After creating more than 1000 files in root directory on ext4 of bigalloc,
the kernel reports many error messages like:

[181126.730911] EXT4-fs error (device sda4): ext4_ind_map_blocks:1015: inode #2: comm falloc: Can't allocate blocks for non-extent mapped inodes with bigalloc
[181126.735945] EXT4-fs error (device sda4): ext4_ind_map_blocks:1015: inode #2: comm falloc: Can't allocate blocks for non-extent mapped inodes with bigalloc

because the root inode of a new ext4 filesystem is type of block-mapped
even use mke2fs with "-O extent,bigalloc".

That reminds me of a question I had with bigalloc - are htree directories supported with bigalloc?  For a 1MB bigalloc chunksize it would mean a fanout of 256k, or a maximum directory size of 256GB with only a single level.

Any thoughts about increasing the directory size beyond 2GB?

Cheers, Andeas