Class: RailsPulse::Dashboard::Charts::P95ResponseTime

Inherits:
Object
  • Object
show all
Defined in:
app/models/rails_pulse/dashboard/charts/p95_response_time.rb

Instance Method Summary collapse

Instance Method Details

#to_chart_data ⇒ Object 



5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
 
# File 'app/models/rails_pulse/dashboard/charts/p95_response_time.rb', line 5

def to_chart_data
  start_date = 2.weeks.ago.beginning_of_day

  # Performance optimization: Single query instead of N+1 queries (15 queries -> 1 query)
  # Fetch all requests for 2-week period, pre-sorted by date and duration
  # For optimal performance, ensure index exists: (occurred_at, duration)
  requests_by_day = RailsPulse::Request
    .where(occurred_at: start_date..)
    .select("occurred_at, duration, DATE(occurred_at) as request_date")
    .order("request_date, duration")
    .group_by { |r| r.request_date.to_date }

  # Generate all dates in range and calculate P95 for each
  (start_date.to_date..Time.current.to_date).each_with_object({}) do |date, hash|
    day_requests = requests_by_day[date] || []

    if day_requests.empty?
      p95_value = 0
    else
      # Calculate P95 from in-memory sorted array (already sorted by DB)
      count = day_requests.length
      p95_index = (count * 0.95).ceil - 1
      p95_value = day_requests[p95_index].duration.round(0)
    end

    formatted_date = date.strftime("%b %-d")
    hash[formatted_date] = p95_value
  end
end