promql: add benchmark for match against blank string
Blank strings are not handled efficiently by tsdb.
@@ -174,6 +174,15 @@ func rangeQueryCases() []benchCase {
{
expr: "a_X + on(l) group_right a_one",
},
+ // Label compared to blank string.
+ {
+ expr: "count({__name__!=\"\"})",
+ steps: 1,
+ },
+ {
+ expr: "count({__name__!=\"\",l=\"\"})",
+ steps: 1,
+ },
}
// X in an expr will be replaced by different metric sizes.
