On Tue, Jun 11, 2013 at 03:05:07PM +0000, OS Engineering wrote: ...
> Dm-cache commits on-disk metadata every time a REQ_SYNC or REQ_FUA > bio is written. If no such requests are made then it commits > metadata once every second. If power is lost, it may lose some > recent writes. Not true (though it is true for thinp, which may be where you got this idea?). For caching we have to commit whenever data is moved about, otherwise a crash could result in us reading data that is not just out of date (acceptable for some), but used to belong to a totally different part of the device (always unacceptable). - Joe -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
