The behavior for querying tag values with an empty string was originally
fixed in #6283, but it also added a performance problem when the
cardinality of the tag was high. Since a call to `Union()` or `Reject()`
would happen for every series key and it would be called N times for N
cardinality, the comparisons against a blank string were unnecessarily
slow with large memory allocations.
This optimizes these queries so it doesn't use those methods anymore.
Those methods are still useful and used when combining AND and OR
clauses, but they aren't useful when finding the series ids for a single
clause. These methods were unnecessary anyway because the series ids for
the tags were unique anyway and didn't have to be merged as a set.
Instead of having the parser set the defaults, the command will set the
defaults so that the constants for that are actually used. This way we
can also identify which things the user provided and which ones we are
filling with default values.
This allows the meta client to be able to make smarter decisions when
determining if the user requested a conflict or if the requested
capabilities match with what is currently available. If you just say
`CREATE DATABASE WITH NAME myrp`, the user doesn't really care what the
duration of the retention policy is and just wants to use the default.
Now, we can use that information to determine if an existing retention
policy would conflict with what the user requested rather than returning
an error if a default value ever gets changed since the meta client
command can communicate intent more easily.
We added `SHARD DURATION` as an extra option, but forgot to increase the
maximum number of allowable options from 3 to 4. So if 4 options were
used, the last one was ignored. This was commonly `DEFAULT`, but it
could have been any of the options.
Negative timestamps are now supported. We also now refuse two
nanoseconds that are at the edge of the minimum time window. One of the
nanoseconds we do not accept is because we need MinInt64 to be used for
some internal comparisons in the TSM engine and it was causing an
underflow when we subtracted one from the minimum time. The second is so
we can have one minimum time that signifies the default minimum that
nobody can write to (so we can implicitly rewrite the timestamp on
aggregate queries) but still use the explicit timestamp if it is given
to us by the user. We aren't able to tell the difference between if the
user provided it or if it was implicit without those values being
different.
If the default minimum time is used with an aggregate query, we rewrite
the time to be the epoch for backwards compatibility since we believe
that's more important than supporting that extra nanosecond.
Jonathan A. Sternberg
Jason Wilder
Nathaniel Cook
Nathaniel Cook
Jason Wilder
Gunnar
gunnaraasen
Edd Robinson
Andy Feller
Ben Johnson
Ashish Gaurav
rw
Mark Rushakoff
Yaser Alraddadi