Lock-Free Read Pattern for Hot Counters (Approximate)

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                  class ViewCounter
  def bump(snip_id)
    Redis.current.incr("snip:views:#{snip_id}")
  end
end

                  class ViewCounterFlushJob < ApplicationJob
  queue_as :maintenance

  def perform
    keys = Redis.current.keys('snip:views:*')
    keys.each do |key|
      snip_id = key.split(':').last.to_i
      delta = Redis.current.get(key).to_i
      next if delta.zero?

      Snip.where(id: snip_id).update_all("views = views + #{delta}")
      Redis.current.del(key)
    end
  end
end

Sometimes exact counters aren’t worth the write cost. For high-traffic views, track increments in Redis and periodically aggregate into the DB. It’s an operational tradeoff that can dramatically reduce DB pressure.

Sarah Chen

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Lock-Free Read Pattern for Hot Counters (Approximate)

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