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ext4 RAID5チューニングオプションはLVMで役立ちますか？

4つのLVをホストするVGの唯一のPVであるmdadmRAID5を備えたシステムでシステムをセットアップしています。

私がファイルシステムを作るとき、mkfs.ext4-Eオプションは役に立ちますか？それとも、LVMシェナニガンのために、その効果を知ることはできませんか？

-E extended-options
    Set extended options for the filesystem. Extended options are comma separated, and may take an argument using the equals ('=') sign. The -E option used to be -R in earlier versions of mke2fs. The -R option is still accepted for backwards compatibility. The following extended options are supported:  
stride=stride-size
    Configure the filesystem for a RAID array with stride-size filesystem blocks. This is the number of blocks read or written to disk before moving to the next disk, which is sometimes referred to as the chunk size. This mostly affects placement of filesystem metadata like bitmaps at mke2fs time to avoid placing them on a single disk, which can hurt performance. It may also be used by the block allocator. 
stripe-width=stripe-width
    Configure the filesystem for a RAID array with stripe-width filesystem blocks per stripe. This is typically stride-size * N, where N is the number of data-bearing disks in the RAID (e.g. for RAID 5 there is one parity disk, so N will be the number of disks in the array minus 1). This allows the block allocator to prevent read-modify-write of the parity in a RAID stripe if possible when the data is written.
performancelvmmdadmraid5ext4
2
OmnipotentEntity

これは、PVがRAIDチャンクサイズにアラインされていることを確認する場合にのみ意味があります（LVは自動的に調整される必要があります）。あなたはそれをチェックすることができます

pvs -o pe_start,pv_name --units s
dmsetup table name # with name what you see in /dev/mapper
3
Hauke Laging