On 10/02/2009, at 10:30 AM, Paul Davis wrote:
Alas it is true, if you have a system that has operating characteristics that involved a write load that far outweighs the read load
I don't think it has to far outweigh it, just exceed it. And in any case, that's assuming that there's a single reader. With replication you might have many readers doing duplicate reads, which means that the effective read rate w.r.t the write rate is divided by the number readers.
For example consider that you have 100 replication readers. Each reader will advance at 1/100'th the rate of a single reader. So the write rate only has to be > 1% of the theoretical read rate to exceed the effective read rate/progress of the individual replicators.
And that's ignoring the fact that the effective read rate for replication is dependent on bandwidth and connectivity e.g throughput is not the same as raw read rate in any case.
Antony Blakey ------------- CTO, Linkuistics Pty Ltd Ph: 0438 840 787 All that is required for evil to triumph is that good men do nothing.
