Re: FSFS propaganda

Greg Hudson <ghudson@MIT.EDU> writes:

> If a process terminates abnormally during a commit operation, it will
> leave behind a stale transaction, which will not interfere with
> operation and which can be removed with a normal recursive delete
> operation.

Another point to discuss would be a machine crash. When a process
writes a file it generally writes it to the OS cache, and the OS
itself is responsible for flushing the cache to disk. A process can
use fsync(2) to force a flush, but if it doesn't explicitly flush and
the machine crashes shortly after the commit completes then data may
be lost.

The BDB backend has DB_TXN_NOSYNC to control whether the process
explicitly flushes, I'm guessing FSFS behaves more like BDB with
DB_TXN_NOSYNC set.

-- 
Philip Martin
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@subversion.tigris.org
For additional commands, e-mail: dev-help@subversion.tigris.org