OOOHeadIndexReader was using the headIndexReader PostingsForMatchers()
and LabelValues() implementation which lead to a very subtle bug that
led to wrong query results.
headIndexReader LabelValues() implementation checks if the query
timerange overlaps with the head maxt and mint and if it doesnt it
returns an empty list of values. Since this code was also used by the
ooo head it led to wrong results that we were not able to see in tests
because our queries where always from MinInt64 to MaxInt64. This commit
also adds a new test that performs multiple time range queries to make
sure this never happens again.
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
This implementation is based on this design doc:
https://docs.google.com/document/d/1Kppm7qL9C-BJB1j6yb6-9ObG3AbdZnFUBYPNNWwDBYM/edit?usp=sharing
This commit adds support to accept out-of-order ("OOO") sample into the TSDB
up to a configurable time allowance. If OOO is enabled, overlapping querying
are automatically enabled.
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
Co-authored-by: Jesus Vazquez <jesus.vazquez@grafana.com>
Co-authored-by: Ganesh Vernekar <ganeshvern@gmail.com>
Co-authored-by: Dieter Plaetinck <dieter@grafana.com>
