Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Lars beat me to this but anyway... On 2009-12-10 13:23, Beck Ingmar wrote: > > Hi Florian, > > why improves bonding of the replication-connection not the performance. I did not say that. :) I said round-robin bonding _over 4 NICs_ would be detrimental to performance. > We currently have a direct connection for the 1 Gb DRBD replication and > I > wanted to activate an active-active bonding (with a further LAN-port). I > would expect nearly double of replication-performance. All of the following applies to DRBD Connected in protocol C: - With 1 GBit Ethernet link, you can do about 110 MB/s (provided your storage subsystem has that bandwidth); - With 2 GBit links bonded in round-robin mode, you top out at around 160-170 MB/s (even then you may have to tune kernel TCP parameters); - with 3 Gbit links, your throughput will drop down to around 110 MB/s; - with 4 links or more, you will get _significantly less_ throughput than a single unbonded link. Reason for all this: TCP reordering. > Or depends it on whether the connection between the nodes directly or > via 1-n switches. I am talking about back-to-back connections. Switches could make it worse. Cheers, Florian -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 260 bytes Desc: OpenPGP digital signature URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20091210/9d90fc23/attachment.pgp>