Re: [PATCH] ext4: Protect group inode free counting with group lock.

[Tao Ma <tm@tao.ma>]

On 05/29/2012 08:39 PM, Ted Ts'o wrote:
> On Mon, May 28, 2012 at 11:57:59PM -0600, Andreas Dilger wrote:
>>> We are just disabling the uninit_bg so as to let the block group
>>> initialization happen in the mkfs time. I don't know why the checksum is
>>> also disabled by ^uninit_bg.
>>
>> The checksum is controlled by uninit_bg, because there was a need to
>> ensure the bg_itable_unused count and the UNINIT flags could be
>> trusted when doing an e2fsck.
>>
>> If you don't want to do lazy inode table initialization, that is
>> disabled by "mke2fs -E lazy_itable_init=0".
> 
> You can also disable whether or not lazy inode table initialization
> happens by default via /etc/mke2fs.conf.  At work we have a very
> fairly havily modified /etc/mke2fs.conf which has our
> production-specific mke2fs parameters defined, so that someone who
> runs mke2fs by hand will get the same result at as the automated
> systems.
> 
> I can easily see how if you are trying for predictable latency
> numbers, disabling lazy inode table initialization makes a huge amount
> of sense.  I'd recommend doing it via /etc/mke2fs.conf, though.
OK, thank you all for the good suggestion.

Thanks
Tao