Block size

[Patrick Dupre]

On Sat, 23 Oct 2010, JD wrote:

>  On 10/23/2010 02:49 PM, Patrick Dupre wrote:
>> On Sat, 23 Oct 2010, Patrick Dupre wrote:
>>
>>> Hello,
>>>
>>> On a logical partition I am unable to set the block size to 1024 !
>>> I formatted the partition mke2fs /dev/VG1/part1 -b 1024 -t ext4
>>> and when I do a
>>> blockbsz --getbsz or mke2fs -n
>>> I get 4096 !
>>> I also tried 2048 with the same result.
>> But dumpe2fs gives the right answer !
>>
>>>
>>> Is it related to the logical partition ?
>>>
>>> Thank.
>>>
>>>
>>
> You have to be aware that selecting such a small
> block size means that the FS will be allocating
> at least 256 bytes of inode space per 1K data block.
> So, the amount of space for on-disk metadata is about
> 25% of the space for data blocks. This is OK if you have
> a lot of small files about 1 to 4k in size. Buf it most of
> your files are much larger than 1kb, then you have
> wasted a lot of disk space for inodes that may never
> be used.
Is there a tool to optimize the block size ?
Determination of the average file size ?

Thank.

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  Patrick DUPRÉ                      |   |
  Department of Chemistry            |   |  Phone: (44)-(0)-1904-434384
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