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, Oct 01, 2008 at 10:41:51AM +0200, Robert wrote: > Hello list, > > the drbdmeta command states that the the dump-md command returns the > activity log also: > > dump-md > > Dumps the whole contents of the meta data storage including the stored > bit-map and activity-log, in a textual representation. > > However, where can the AL be found in the output of dump-md ? > Where's the AL ? apparently missing. documentation bug, I'd say. > And one more question regarding the AL: > > The DRBD Manual states: > As DRBD detects write I/O on a disconnected device, and hence starts > setting bits in the quick-sync bitmap, it does so in RAM — thus avoiding > expensive synchronous metadata I/O operations. Only when the > corresponding blocks turn cold (that is, expire from the Activity Log > <http://www.drbd.org/users-guide/s-activity-log.html>), DRBD makes the > appropriate modifications in an on-disk representation of the quick-sync > bitmap. Likewise, if the resource happens to be manually shut down on > the remaining node while disconnected, DRBD flushes the /complete/ > quick-sync bitmap out to persistent storage. > > The interesting part is [...] Only when the corresponding blocks turn > cold (that is, expire from the Activity Log > <http://www.drbd.org/users-guide/s-activity-log.html>) [...] > > Does the AL Extend turn cold ONLY if the nuber of open AL Extends is > reached and a AL Extend has to be reused (so to speak LRU) (I have > written so much data on disk, that all configured al-extend are used > and I have to write to a block that is not covered by a AL Extend > yet) or not "so much data", but "to so many areas". you can write as many exabytes to the same sector as you want, and the AL will not change. > does the AL also expire AL Extend based on a timeout mechanism (so to > speak LRU+timeout) (e.g. a AL Extend not written to in 5 seconds is > expired). no, it does not. but we will eventually implement something like that. somewhen. -- : 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