Richard Hipp, on 11/02/2012 08:24 AM wrote:
SQLite cares. SQLite is an in-process, transaction, zero-configuration database that is estimated to be used by over 1 million distinct applications and to be have over 2 billion deployments. SQLite uses ordinary disk files in ordinary directories, often selected by the end-user. There is no system administrator with SQLite, so there is no opportunity to use a dedicated filesystem with special mount options. SQLite uses fsync() as a write barrier to assure consistency following a power loss. In addition, we do everything we can to maximize the amount of time after the fsync() before we actually do another write where order matters, in the hopes that the writes will still be ordered on platforms where fsync() is ignored for whatever reason. Even so, we believe we could get a significant performance boost and reliability improvement if we had a reliable write barrier.
I would suggest you to forget word "barrier" for productivity sake. You don't want barriers and confusion they bring. You want instead access to storage accelerated cache sync, commands ordering and atomic attributes/operations. See my other today's e-mail about those.
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