Installation guide

Glossary

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available at mkfs time as well. Doing well-aligned allocation I/O can

avoid inefficient read-modify-write cycles on the underlying storage.

Write Barriers A method to enforce consistent I/O ordering on storage devices which

have volatile write caches. Barriers must be used to ensure that

after a power loss, the ordering guarantees required by metadata

journalling are not violated due to the storage hardware writing

out blocks from its volatile write cache in a different order than the

operating system requested.