Writing the snapshot would deduplicate the snapshot points
while still holding the engine write-lock. This can be expensive
under high load and cause writes to back up and OOM the server.
Instead, grab the snapshot under the lock and dedup it after releasing
the lock.
Possible fix for #5442
Possible fix for #5437. meta.Client.RetentionPolicy acquired a read-lock and
then called Database which called data() which acquired a read-lock again.
If a write lock was taken between these two read-locks (likely by Authenticate),
the write-lock would block, and the second read-lock would also block
causing a dead-lock.
Previously if you issued a CQ with a resample interval higher than the
query interval, such as the following:
CREATE CONTINUOUS QUERY cq ON db
RESAMPLE EVERY 4m
BEGIN
SELECT mean(value) INTO cpu_mean FROM cpu GROUP BY time(2m)
END
This would result in strange behavior because the FOR value defaulted to
the GROUP BY interval and the minimum time passing before a CQ ran was
also the resample interval, so it wouldn't run the appropriate intervals
even if you set the resample duration to a higher value.
This tweaks the CQ runner to set the minimum interval before a bucket
becomes capable of running to the lower of the query interval or the
resample interval instead of always using the resample interval.
It also sets the default resample duration to be the higher value of the
query interval or the resample interval so the above query gets a
default of 4m instead of 2m and will execute 2 queries every 4 minutes.
If you manually set the resample duration to a lower value than the
resample interval, the old behavior will still happen and should be
considered an error.
This also makes trying to create a continuous query with a resample
duration of below the resample interval or query interval (whichever is
higher) as an error returned by the parser.
Fixes#5286.
If a bind-address of :8088 is used, cluster nodes cannot
connect to those nodes because there is no hostname portion
of the address. When we see a bind-address without a hostname,
use the os hostname or localhost if that fails if it is not specified
in the config already.
* Improve the ping endpoint so that it can optionally check for leader agreement across all meta servers
* Add Ping method to the meta client
* Fix ClusterID tests
* Remove WaitForLeader from meta client and remove unnecessary references to it
* Updated CreateShardGroup to not return an error if it already exists so it's idempotent
* Removed old test making sure you can't delete the default RP. You can delete it now, there was no reason to disallow it.
* Wired up the UpdateRetentionPolicy functionality
Jason Wilder
Jason Wilder
David Norton
Jonathan A. Sternberg
Jonathan A. Sternberg
Cory LaNou
Ross McDonald
Paul Dix