Filesystem with 1Mb block?

Question

I'd like to make a partition for keeping ISO images of nightly builds. Most of files will be bigger than 1Mb. Unfortunately ext2/ext3/ext4 supports only 4Kb blocks.

# mkfs.ext4 -b 1048576 -L DISTR -m 0 /dev/sdb1 
mkfs.ext4: invalid block size - 1048576

Is there any other reliable filesystem that can be used in order to reduce fragmentation?

Answer 1

man mke2fs states

Valid block-size values are 1024, 2048 and 4096 bytes per block

If we have a look to fs/block_dev.c we could find following:

int set_blocksize(struct block_device *bdev, int size)
{
        /* Size must be a power of two, and between 512 and PAGE_SIZE */
        if (size > PAGE_SIZE || size < 512 || !is_power_of_2(size))
                return -EINVAL;

And finally we can determine PAGE_SIZE:

# getconf -a| grep PAGE_SIZE
PAGE_SIZE                          4096