On Sun, 2010-11-21 at 14:07 -0500, Valdis.Kletnieks@xxxxxx wrote: > On Fri, 19 Nov 2010 09:53:52 EST, Mark Lord said: > > On 10-11-19 09:40 AM, Chris Mason wrote: > > > > > > We've been told that online and constant trimming is the default in > > > windows7. The ssds are most likely to just start ignoring the trims > > > they can't service efficiently. > > > > Win7 collects multiple TRIM ranges over time and batches them as single TRIMs > > (as reported to me by an SSD vendor who traced it with a SATA analyzer, > > and who also apparently has "inside info"). > > What should happen if we have (for instance) a "collect 64 trims at a time" policy, > and the system crashes at trim number 47? (Probably not an issue if you're > doing non-deterministic trim, but is an exposure if you're relying on deterministic > trim for security reasons) I think it's about the third time in the thread this has been said but just in case anyone else missed it: TRIM != SECURE ERASE. TRIM/UNMAP/WRITE_SAME are used to provide optional information about which blocks the filesystem doesn't care about. They have no bearing on information security which is preserved by separate mechanisms. James -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html