Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Hello list, I'm evaluating DRBD performance in various scenarios right now - values as expected except for one value. 100% random write (8k) When doing 100% wandom write of 8k with i/o meter I get (repeatable): 218 TPS for the lower level LVM volume (/dev/vg_something/drbd0) 111 TPS with a DRBD device in connected mode (Protocol A over cross over GBIT) 99 TPS with the same DRBD device beeing disconnected (StandAlone Primary/unknown - manually disconnected the device with "drbdadm disconnect all") The Filesystem is XFS The Hardware is BBU supported 3Ware with 2x SATA HDD's and write cache enabled. Config includes: no-disk-flushes; no-md-flushes; al-extents 1021; I wonder: - Why is DRBD in connetced mode faster than in disconnected mode ? - Why is the lower level LVM device so much faster (mount options are the same) ? Any hints ? Regards, Robert