On Mon, 12 Apr 2010 14:33:44 -0700
Mahadev Konar <maha...@yahoo-inc.com> wrote:
> Hi Kevin,
>
> Thanks for the info. Could you cut and paste the code you are using
> that prints the view info?
> That would help. We can then create a jira and follow up on that.
>
> Also, a zookeeper client can never go back in time (even if its gets
> disconnected and connected back to another server).
>
> Thanks
> mahadev
Ah, sorry, I meant to include that last time.
This is the function I use to read the cversion:
static int32_t read_path_cversion(zhandle_t *zkhandle, const char
*path) {
struct Stat stat;
int zoo_result;
memset(&stat, 0, sizeof(struct Stat));
zoo_result = zoo_exists(zkhandle, path, 0, &stat);
if (zoo_result != ZOK) {
return -1;
}
return stat.cversion;
}
It gets called by this function, which is called whenever the client
(re)connects to the server or when the watch on the group node gets
triggered:
static int process_membership_change(zhandle_t *zkhandle, zk_comm_t
*context, const char *path) {
struct String_vector children;
int32_t view_before = 0;
int32_t view_after = view_before + 1;
int zoo_result = 0;
int i;
while (view_before != view_after) {
view_before = read_path_cversion(zkhandle, path);
zoo_result = zoo_get_children(zkhandle, path, 1, &children);
if (zoo_result != ZOK) {
return zoo_result;
}
view_after = read_path_cversion(zkhandle, path);
}
printlog(LOG_CRITICAL, "ZK(%" PRIu32 "): %u Beginning new view #%"
PRId32 ". Unsetting panic...\n", context->comm->id, time(NULL),
view_after);
(call application function to restart with group #view_after)
...
More application logic
...
}
Let me know if any other details would be helpful.
-Kevin
