[Ocfs2-users] how to find out the real size of a reflink ?

[Lentes, Bernd]

----- On Jan 14, 2021, at 2:50 AM, Gang He ghe at suse.com wrote:

> Hi Lentes,
> 
> see my comments inline.

>> 
>> Some questions:
>> 
>> What is a cluster ?
>> What is an extent ?
> In the traditional file system, a file consists of meta-data blocks and
> data blocks, but for ocfs2 file system, a file consists of meta-data
> blocks and data clusters, the cluster size can greater than the block
> size to save meta-data block consumption.
> The file data is contained by clusters, the file meta data is contained
> by blocks, there are few kind of meta-data blocks, e.g. extent blocks
> looks like to store cluster pointers.
> 

What is the size of a cluster ? 1MB ?
And what is an extent ?

Thanks.

Bernd
Helmholtz Zentrum München

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