{ "cells": [ { "cell_type": "code", "execution_count": 1, "id": "ab5cd7d1-1a57-46fc-8282-dae0a6cc2944", "metadata": {}, "outputs": [], "source": [ "import matplotlib.pyplot as plt\n", "import numpy as np\n", "import random\n", "import pandas as pd\n", "import itertools\n", "from tqdm import tqdm" ] }, { "cell_type": "code", "execution_count": 2, "id": "3d1ad0b9-f6a8-4e98-84aa-6e02e4279954", "metadata": {}, "outputs": [], "source": [ "SEED = 42\n", "np.random.seed(SEED)\n", "random.seed(SEED)\n", "\n", "ZIPF_CONSTANT = 2" ] }, { "cell_type": "code", "execution_count": 3, "id": "5a27d416-8f98-4814-af9e-6c6bef95f4ef", "metadata": {}, "outputs": [], "source": [ "def eta_star(db_object_count, c_f, cache_sz, c_delta, lambda_vals):\n", " num = (db_object_count * c_f - cache_sz * c_delta)\n", " denom = np.sum(1.0/lambda_vals)\n", " if denom == 0:\n", " print(\"sum(1.0/lambda_vals) == 0\")\n", " print(db_object_count, c_f, cache_sz, c_delta, lambda_vals)\n", " return max(0, num/denom)" ] }, { "cell_type": "code", "execution_count": 4, "id": "6276a9ce-f839-4fe6-90f2-2195cf065fc8", "metadata": {}, "outputs": [], "source": [ "def h_i_star(c_f, eta, lambda_vals, c_delta):\n", " optimized_hitrate = (c_f - (eta/lambda_vals)) / c_delta\n", " return optimized_hitrate" ] }, { "cell_type": "code", "execution_count": 5, "id": "dcd31a8c-6864-4b9a-8bb3-998f0c32baf6", "metadata": {}, "outputs": [], "source": [ "def get_index_of_furthest_hitrate_from_boundary(hitrates):\n", " lower_bound_violation = hitrates[(hitrates < 0)]\n", " upper_bound_violation = hitrates[(hitrates > 1)]\n", " smallest_delta = np.abs(np.min(lower_bound_violation))\n", " biggest_delta = np.max(upper_bound_violation) - 1\n", " if smallest_delta > biggest_delta:\n", " print(smallest_delta)\n", " index = np.where(hitrates == np.min(local_hitrates))[0][0]\n", " return index\n", " else:\n", " \n", " index = np.where(hitrates == np.max(local_hitrates))[0][0]\n", " return index" ] }, { "cell_type": "code", "execution_count": 6, "id": "9d774304-ae68-43b3-a76a-e970c06c5236", "metadata": {}, "outputs": [], "source": [ "def get_index_of_furthest_hitrate_from_boundary(hitrates):\n", " outside_bounds = (hitrates < 0) | (hitrates > 1)\n", " distances = np.where(outside_bounds, np.maximum(np.abs(hitrates - 0), np.abs(hitrates - 1)), -np.inf)\n", " index = np.argmax(distances)\n", " return index" ] }, { "cell_type": "code", "execution_count": 7, "id": "0e21c26f-058a-4e56-a5ad-1c47bf28656c", "metadata": { "scrolled": true }, "outputs": [], "source": [ "def optimize_hitrates(db_object_count, cache_size, c_f, c_delta, lambda_vals):\n", " optimized_hitrates = np.zeros(db_object_count)\n", " current_db_object_count = db_object_count\n", " current_cache_size = cache_size\n", " \n", " differenc_set = np.arange(db_object_count)\n", " fix_i = []\n", " while True:\n", " if current_db_object_count == 0:\n", " if current_cache_size > 0:\n", " # print(\"Re-optimize objects with optimal hitrate of 0.\")\n", " differenc_set = np.where(optimized_hitrates == 0)[0]\n", " fix_i = np.setdiff1d(np.arange(db_object_count), differenc_set).tolist()\n", " current_db_object_count = len(differenc_set)\n", " continue\n", " else:\n", " # print(\"Stop optimization.\")\n", " optimized_hitrates[differenc_set] = 0\n", " break\n", " \n", " eta = eta_star(current_db_object_count, c_f, current_cache_size, c_delta, lambda_vals[differenc_set])\n", " optimized_hitrates[differenc_set] = h_i_star(c_f, eta, lambda_vals[differenc_set], c_delta)\n", "\n", " if eta < 0:\n", " # print(\"eta was negative.\")\n", " current_cache_size = current_db_object_count * c_f / c_delta # Adjust cache size for next iteration\n", " continue\n", " \n", " if len((optimized_hitrates[differenc_set])[((optimized_hitrates[differenc_set]) < 0) | ((optimized_hitrates[differenc_set])> 1)]) == 0:\n", " # print(\"All values optimized.\")\n", " break\n", " \n", " max_outbound_index = get_index_of_furthest_hitrate_from_boundary(optimized_hitrates)\n", " fix_i.append(max_outbound_index)\n", " differenc_set = np.setdiff1d(np.arange(db_object_count), fix_i)\n", " \n", " old_hitrate = optimized_hitrates[max_outbound_index]\n", " optimized_hitrates[max_outbound_index] = (1 if optimized_hitrates[max_outbound_index] > 1 else 0)\n", " \n", " current_db_object_count -= 1\n", " current_cache_size -= optimized_hitrates[max_outbound_index]\n", " return optimized_hitrates" ] }, { "cell_type": "code", "execution_count": 8, "id": "b6bf3329-3a63-4807-ab8b-8a54f824f47e", "metadata": {}, "outputs": [], "source": [ "def objective_function(optimized_hitrates, c_f, c_delta, lambda_vals):\n", " return np.sum(lambda_vals*(1-optimized_hitrates)*c_f+0.5*np.power(optimized_hitrates,2)*c_delta)" ] }, { "cell_type": "code", "execution_count": 9, "id": "7a998837-72b8-4039-95a5-ca8d9c8e65ab", "metadata": {}, "outputs": [], "source": [ "# Perform grid search\n", "def grid_search(db_object_counts, cache_sizes, c_f_values, c_delta_values):\n", " best_objective = float('inf')\n", " best_params = None\n", "\n", " # Iterate through all combinations of parameters\n", " for db_object_count, cache_size, c_f, c_delta in tqdm(itertools.product(db_object_counts, cache_sizes, c_f_values, c_delta_values), total=len(db_object_counts) * len(cache_sizes) * len(c_f_values) * len(c_delta_values), desc=\"Grid Search Progress\"):\n", " if db_object_count < cache_size:\n", " continue\n", " lambda_vals = np.array([np.random.zipf(ZIPF_CONSTANT) for i in np.arange(1, db_object_count + 1,1)])\n", " # print(db_object_count, cache_size, c_f, c_delta)\n", " # Call the optimization function\n", " optimized_hitrates = optimize_hitrates(db_object_count, cache_size, c_f, c_delta, lambda_vals)\n", "\n", " # Compute the objective function\n", " objective = objective_function(optimized_hitrates, c_f, c_delta, lambda_vals)\n", " \n", " # Track the best (minimum) objective and corresponding parameters\n", " if objective < best_objective:\n", " best_objective = objective\n", " best_params = (db_object_count, cache_size, c_f, c_delta)\n", "\n", " return best_objective, best_params" ] }, { "cell_type": "code", "execution_count": 10, "id": "a271b52d-1f24-4670-ae3f-af5dd9096a2f", "metadata": { "scrolled": true }, "outputs": [ { "name": "stderr", "output_type": "stream", "text": [ "Grid Search Progress: 100%|█████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████| 64152/64152 [12:27<00:00, 85.87it/s]" ] }, { "name": "stdout", "output_type": "stream", "text": [ "CPU times: user 12min 16s, sys: 11.5 s, total: 12min 28s\n", "Wall time: 12min 27s\n" ] }, { "name": "stderr", "output_type": "stream", "text": [ "\n" ] } ], "source": [ "%%time\n", "\n", "# Define the grid search space\n", "test_ratios = np.array([0.1, 0.2, 0.5, 0.7, 1, 1.5, 2, 5, 10])\n", "db_object_count_values = np.round(np.array([10, 15, 30, 100, 200, 500]))\n", "cache_size_values = np.unique(np.round(np.array([db_object_count_values * i for i in test_ratios]).flatten()))\n", "c_f_values = np.array([0.1, 0.2, 0.5, 0.7, 1, 1.5, 2, 5, 10])\n", "c_delta_values = np.unique(np.array([c_f_values * i for i in test_ratios]).flatten())\n", "\n", "best_objective, best_params = grid_search(db_object_count_values, cache_size_values, c_f_values, c_delta_values)" ] }, { "cell_type": "code", "execution_count": 11, "id": "b2f625d0-ebe0-4a5d-92ff-7de03942ef51", "metadata": {}, "outputs": [ { "data": { "text/plain": [ "(0.05000000000000002, (10, 10.0, 1.5, 0.010000000000000002))" ] }, "execution_count": 11, "metadata": {}, "output_type": "execute_result" } ], "source": [ "best_objective, best_params " ] }, { "cell_type": "code", "execution_count": null, "id": "86a23d02-6f14-4d4d-ad8a-39084ea69151", "metadata": {}, "outputs": [], "source": [] } ], "metadata": { "kernelspec": { "display_name": "graphs", "language": "python", "name": "graphs" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.12.7" } }, "nbformat": 4, "nbformat_minor": 5 }