Hi, I'm a long time user of both PostgreSQL and LVM. So far I've been quite happy with both. But a recent thread on the PostgreSQL list made me unconfortable. What is this thing they're referring to, fsync()'s being ignored? Makes me feel like I'm running on thin ice, without even knowing. Before I start phasing out LVM from all my PostgreSQL installations (as they suggest), I'd like to hear some kind of confirmation. This is quite scary. http://archives.postgresql.org/pgsql-general/2009-03/msg00204.php In my understanding: fsync(): force data from OS memory to disk (ending up in the disk cache) write barrier: force data from disk cache to disk platters If you disable write-back cache on the disks, you no longer need write barriers. But apparently they claim LVM being unsafe even with disks caches in write-thru mode, which surprises me a lot. .TM. _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
