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I have some alignment errors on my Fusion Drive after? reorder the CoreStorage.

For some weeks ago I got my purchased iMac 27 and made out, that the index order of the SSD and HDD drives are wrong. At index 0 there was the hdd and on index 1 pointed to the SSD. The problem was that the Operations during the work on the mac was very slow.

So I made a new clean install, created a new CoreStorage and reordered the Fusion Drive, so that the SSD is at index 0. Please look what I mean:

diskutil cs list    

CoreStorage logical volume groups (1 found)
|
+-- Logical Volume Group 
    =========================================================
    Name:         OSX-MacintoshLVG
    Status:       Online
    Size:         1022898851840 B (1.0 TB)
    Free Space:   45056 B (45.1 KB)
    |
    +-< Physical Volume 
    |   ----------------------------------------------------
    |   Index:    0
    |   Disk:     disk1s2
    |   Status:   Online
    |   Size:     23553724416 B (23.6 GB)
    |
    +-< Physical Volume 
    |   ----------------------------------------------------
    |   Index:    1
    |   Disk:     disk0s2
    |   Status:   Online
    |   Size:     999345127424 B (999.3 GB)
    |
    +-> Logical Volume Family 
        ----------------------------------------------------------
        Encryption Type:         None
        |
        +-> Logical Volume 
            ---------------------------------------------------
            Disk:                  disk2
            Status:                Online
            Size (Total):          1021994074112 B (1.0 TB)
            Revertible:            No
            LV Name:               Macintosh HD
            Volume Name:           Macintosh HD
            Content Hint:          Apple_HFS
            LVG Type:              Fusion, Sparse

I wrote after reorder because I'm not sure that was before I create the new CoreStorage.

After made out the alignment errors I checke the block size of the two drives that differs!

HDD:

diskutil info /dev/disk0 | grep "Block Size"
   Device Block Size:        512 Bytes

SSD:

diskutil info /dev/disk1 | grep "Block Size"
   Device Block Size:        4096 Bytes

I think that's the problem that I've got this errors.

Question 1: Does a method exist to modify the block size of the 512 Bytes drive to 4096 Bytes?

Question 2: Is it possible to lose data caused by the different block sizes (I/O errors)?.

The iMac actually is running without problems, but some of my pdf documents gives me cryptic output if I copy some text from there. I mean if I paste the copied text into another document I got cryptic output.

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