[FTS] perf: date facets query doesn't scale due to extensive garbage collection (top CPU load is 35%)

The average latency of the query is about 3.6 sec.
Single hit takes 25% CPU to process

The maximum throughput is expected to be at least 1.1 queries/sec:
100% / 25% = 4 clients to saturate the CPU
4 clients / 3.6 sec waiting = 1.1 queries/sec

Actual throughput is 0.5 queries/sec and the CPU maximum is 35% for 4+ clients
The bottleneck is garbage collection. The are more than 300 gc events per second when processing the single query. Which totals it to 1000+ events for entire query.
The garbage collection takes about 15% of the query time.

With nearly disabled GC (GOGC=10000) the CPU can be saturated and throughput is up 1.5 queries/sec

This issue isn't related to MB-21452 (high latency of the date facets query). With limited GC impact the latency of the single query is still very high