Requirements for using torn write prevention on Amazon EC2 - Amazon Elastic Compute Cloud
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Requirements for using torn write prevention on Amazon EC2

For torn write prevention to work properly, an I/O operation must meet size, alignment, and boundary requirements, as specified in the NTWPU, NTWGU, NTWBU fields. You must configure your operating system to ensure that the specific storage subsystem (file system, LVM, RAID, etc) does not modify I/O properties down the storage stack, including block merges, splits, or block address relocation, before being submitted to the device.

Torn write prevent has been tested with the following configuration:

  • An instance type and storage type that supports the required block size.

  • Amazon Linux 2 with kernel version 5.10 or later.

  • ext4 with bigalloc enabled and a cluster size of 16 KiB, and the most recent ext4 utilities (e2fsprogs 1.46.5 or later).

  • O_DIRECT file access mode to bypass Linux kernel buffer cache.

Note

You do not need to disable I/O merging for MySQL and MariaDB workloads.