John Groves wrote:
A question for those who know more about xfs internals than me:
If want to create sparse files that XFS can handle efficiently, is there
an optimal minimum sparse chunk size? I can look at an data stream for
null segments and make them sparse, but I presume I shouldn't make 1
byte sparse extents.
No such thing; extents (and holes) are a minimum of one filesystem block, in block multiples. A
sparse file has offsets with no written data that span at least 1 complete filesystem block,
beginning & ending on a block boundary. zeroed data ranges which are sub-block in size are just
zeros written to disk, inside the filesystem block, part of a real extent.
-Eric
File size will range from small to multiple GB,
but large files are the norm.
Thanks,
John Groves
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