we should put in a test for that. it is certainly a plausible
scenario. in theory it will just flow into the next epoch and everything
will be fine, but we should try it and see.
ben
On 10/19/2010 11:33 AM, Sandy Pratt wrote:
Just as a thought experiment, I was pondering the following:
ZK stamps each change to its managed state with a zxid
(http://hadoop.apache.org/zookeeper/docs/r3.2.1/zookeeperInternals.html). That
ID consists of a 64 bit number in which the upper 32 bits are the epoch, which
changes when the leader does, and the bottom 32 bits are a counter, which is
incremented by the leader with every change. If 1000 changes are made to ZK
state each second (which is 1/20th of the peak rate advertised), then the
counter portion will roll over in 2^32 / (86400 * 1000) = 49 days.
Now, assuming that my math is correct, is this an actual concern? For example,
if I'm using ZK to provide locking for a key value store that handles
transactions at about that rate, am I setting myself up for failure?
Thanks,
Sandy
