Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Wed, Nov 12, 2008 at 10:20:08PM +0100, Philipp Reisner wrote: > * Support for using barriers to enforce write ordering on the secondary > node. New config options: no-disk-barrier, no-disk-drain let me add here: if your DRBD lives on a battery backed write cache, and for performance reasons in the past you needed to say "no-disk-flushes", chances are that you now need this "no-disk-barrier" in addition, or throughput may degrade again. do NOT use no-disk-drain if you care for write ordering and there is anything below drbd in the io stack that may re-order writes. to put that the other way around: only use no-disk-drain if you use the no-op io scheduler, AND all the lower level transports involved do not reorder anything before a write is completed as "on stable storage". -- : Lars Ellenberg : LINBIT | Your Way to High Availability : DRBD/HA support and consulting http://www.linbit.com DRBD® and LINBIT® are registered trademarks of LINBIT, Austria. __ please don't Cc me, but send to list -- I'm subscribed