
LizardFS is Pretty Nice - Pneumaticat
https://potatofrom.space/post/lizardfs-is-pretty-nice/
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Annatar
"However, it doesn’t write files whole – it breaks each into 64 MB chunks and
distributes them across its drives."

And what happens when the file is <= 64 MB?

Does it run on illumos / SmartOS?

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Pneumaticat
According to the LizardFS whitepaper [1], the chunks can be _up to_ 64 MB. So
I believe if the file is smaller, the chunk is just as large as necessary.

Looking at some chunk files on my system backs this up:

    
    
      root@rem> ls -l | head
      total 11702880
      -rw-r----- 1 mfs mfs 33558528 Dec 12 18:17 chunk_ec_1_of_2_1_000000000000010C_00000001.mfs                                                
      -rw-r----- 1 mfs mfs    69632 Dec 12 18:12 chunk_ec_1_of_2_1_0000000000000179_00000001.mfs                                                
      -rw-r----- 1 mfs mfs    69632 Dec 12 18:11 chunk_ec_1_of_2_1_0000000000000187_00000001.mfs                                                
      -rw-r----- 1 mfs mfs    69632 Dec 12 18:26 chunk_ec_1_of_2_1_0000000000000194_00000001.mfs                                                
      -rw-r----- 1 mfs mfs    69632 Dec 12 18:06 chunk_ec_1_of_2_1_0000000000000197_00000001.mfs                                                
      -rw-r----- 1 mfs mfs    69632 Dec 12 18:36 chunk_ec_1_of_2_1_00000000000001A1_00000001.mfs                                                
      -rw-r----- 1 mfs mfs    69632 Dec 12 18:03 chunk_ec_1_of_2_1_00000000000001CE_00000001.mfs                                                
      -rw-r----- 1 mfs mfs    69632 Dec 12 18:13 chunk_ec_1_of_2_1_00000000000001D4_00000001.mfs                                                
      -rw-r----- 1 mfs mfs   135168 Dec 12 18:05 chunk_ec_1_of_2_1_0000000000000217_00000001.mfs
    

As for illumos/SmartOS -- maybe? The LizardFS cookbook [2] has a section for
illumos, but there's nothing in it. It should probably work (it's C++), but
there is probably going to have to be manual effort involved.

~~~
Annatar
Now do a test with a file size of exactly 1 non-NULL byte and report back.

If the 1-byte file gets replicated across multiple disks, corrupt one of the
chunks and report back.

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syn0byte
Depends entirely on what replication goals you have setup. My simple cluster
(not EC or XOR) mandates 2 copies per chunk at a minimum. My 1-byte file was
unaffected by a single chunk corruption, even on the node in which the
corruption originated.

