Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Ah! Well, a limit of ~250K/s would be it then! Seriously though, why so low in the age of 1 and 10GigE? I understand you wouldn't want to be responsible for saturation the link but isn't 250K being a little *too* conservative? I have a dedicated crossover cable for this between two 1GigE nvidia NICs. They are quite capable of a pretty quick speed. I'll actually specify the rate and 'drbdadm adjust' appropriately! Ta, Jim ----- Original Message ----- From: "Lars Ellenberg" <lars.ellenberg at linbit.com> To: drbd-user at lists.linbit.com Sent: 22 March 2007 19:49:15 o'clock (GMT) Europe/London Subject: Re: [DRBD-user] Sync rate is 300K/s! On Wed, Mar 21, 2007 at 04:43:58PM +0000, James Vanns wrote: > I have a crossover cable between two machines sporting 1GigE NICs. > With DRBD 8.0.0 I'm getting a sync rate of '376 (320) K/sec' as > reported by /proc/drbd! What gives!? This isn't normal as I had a > better rate with beta 6 (I think). I have not put a cap on the maximum > rate in the configuration file. I have also tried pausing the sync, > adding a cap of ~600M, then resuming the sync all to no avail. > > Anyone else experience this? if by "not put a cap" you mean you did just not specify the "syncer rate", it defaults to ~250K/sec ... against common believe it does _not_ help to specify a ridiculous high rate, it does hurt. if you do not want "to cap", you should put it in the area of what your hardware is capable to deliver. so if you can reasonably expect from your hardware that it will deliver, say, 70 MByte / sec sustained sequential write, and you do not want to reserve anything of that for application usage, you should specify a sync rate of about 70 to 80 M. (rate 600M will probably hurt more than it helps). (and don't forget to "drbdadm adjust") there also are "advanced" tunables, especially max-buffers and unplug-watermark may help. tune carefully, just using maximum settings is not going to be optimal, sometimes even smaller values increase overall performance. if nothing helps, post your hardware (NICs, used driver(version) and io subsystem (and driver/version, if applicable). maybe someone with the same hardware has seen and solved your problems before. -- : Lars Ellenberg Tel +43-1-8178292-0 : : LINBIT Information Technologies GmbH Fax +43-1-8178292-82 : : Vivenotgasse 48, A-1120 Vienna/Europe http://www.linbit.com : __ please use the "List-Reply" function of your email client. _______________________________________________ drbd-user mailing list drbd-user at lists.linbit.com http://lists.linbit.com/mailman/listinfo/drbd-user -- James Vanns Systems Programmer Framestore CFC Ltd.