The next example is wrong too, claiming to show 60 secs, while it shows 600 secs (the default value as well).
The question is still, what is a good value for intervals? Anyone here that uses the Canary that would like to chime in? On Sat, Feb 4, 2017 at 5:40 PM, Ted Yu <[email protected]> wrote: > Brief search on HBASE-4393 didn't reveal why the interval was shortened. > > If you read the first paragraph of: > http://hbase.apache.org/book.html#_run_canary_test_as_daemon_mode > > possibly the reasoning was that canary would exit upon seeing some error > (the first time). > > BTW There was a mismatch in the description for this command: (5 seconds > vs. 50000 milliseconds) > > ${HBASE_HOME}/bin/hbase canary -daemon -interval 50000 -f false > > > On Sat, Feb 4, 2017 at 8:21 AM, Lars George <[email protected]> wrote: > >> Oh right, Ted. An earlier patch attached to the JIRA had 60 secs, the >> last one has 6 secs. Am I reading this right? It hands 6000 into the >> Thread.sleep() call, which takes millisecs. So that makes 6 secs >> between checks, which seems super short, no? I might just dull here. >> >> On Sat, Feb 4, 2017 at 5:00 PM, Ted Yu <[email protected]> wrote: >> > For the default interval , if you were looking at: >> > >> > private static final long DEFAULT_INTERVAL = 6000; >> > >> > The above was from: >> > >> > HBASE-4393 Implement a canary monitoring program >> > >> > which was integrated on Tue Apr 24 07:20:16 2012 >> > >> > FYI >> > >> > On Sat, Feb 4, 2017 at 4:06 AM, Lars George <[email protected]> >> wrote: >> > >> >> Also, the default interval used to be 60 secs, but is now 6 secs. Does >> >> that make sense? Seems awfully short for a default, assuming you have >> >> many regions or servers. >> >> >> >> On Sat, Feb 4, 2017 at 11:54 AM, Lars George <[email protected]> >> >> wrote: >> >> > Hi, >> >> > >> >> > Looking at the Canary tool, it tries to ensure that all canary test >> >> > table regions are spread across all region servers. If that is not the >> >> > case, it calls: >> >> > >> >> > if (numberOfCoveredServers < numberOfServers) { >> >> > admin.balancer(); >> >> > } >> >> > >> >> > I doubt this will help with the StochasticLoadBalancer, which is known >> >> > to consider per-table balancing as one of many factors. In practice, >> >> > the SLB will most likely _not_ distribute the canary regions >> >> > sufficiently, leaving gap in the check. Switching on the per-table >> >> > option is discouraged against to let it do its thing. >> >> > >> >> > Just pointing it out for vetting. >> >> > >> >> > Lars >> >> >>
