feat(tools): Add Zipfian cache testing tool (#640)

* adding cache testing tool

Signed-off-by: Ubuntu <ubuntu@ip-172-31-12-15.us-west-2.compute.internal>

tools/cache_testing.py

@@ -0,0 +1,116 @@
+#!/usr/bin/env python
+
+import redis
+import argparse
+from urllib.parse import urlparse
+import numpy as np
+
+'''
+Run Cache Testing.
+This tool performs cache testing for Dragonfly
+by calling the `incrby` function on a constrained set
+of items, as defined by the user. Additionally, it
+distributes the frequency of `incrby` calls for each
+item based on a Zipfian distribution (with alpha values
+between 0 and 1 being representative of real-life cache
+load scenarios)
+'''
+
+def rand_zipf_generator(n, alpha, count, pipeline):
+    """
+    n: The upper bound of the values to generate a zipfian distribution over
+    (n = 30 would generate a distribution of given alpha from values 1 to 30)
+    alpha: The alpha parameter to be used while creating the Zipfian distribution
+    num_samples: The total number of samples to generate over the Zipfian distribution
+    This is a generator that yields up to count values using a generator.
+    """
+
+    # Calculate Zeta values from 1 to n:
+    tmp = np.power( np.arange(1, n+1), -alpha )
+    zeta = np.r_[0.0, np.cumsum(tmp)]
+
+    # Store the translation map:
+    distMap = [x / zeta[-1] for x in zeta]
+
+    if pipeline == 0:
+        # Generate an array of uniform 0-1 pseudo-random values:
+        u = np.random.random(count)
+
+        # bisect them with distMap
+        v = np.searchsorted(distMap, u)
+
+        samples = [t-1 for t in v]
+
+        for sample in samples:
+            yield sample
+    else:
+        current_count = 0
+        while current_count < count:
+            # Generate an array of uniform 0-1 pseudo-random values, of the pipeline length:
+            u = np.random.random(pipeline)
+
+            # bisect them with distMap
+            v = np.searchsorted(distMap, u)
+
+            samples = [t-1 for t in v]
+            yield samples
+
+            current_count += len(samples)
+
+def update_stats(r, hits, misses, value_index, total_count):
+    """
+    A void function that uses terminal control sequences
+    to update hit/miss ratio stats for the user
+    while the testing tool runs.
+    """
+    percent_complete = (value_index + 1) / total_count
+
+    # Use the terminal control sequence to move the cursor to the beginning of the line
+    print("\r", end="")
+
+    # Print the loading bar and current hit rate
+    print("[{}{}] {:.0f}%, current hit rate: {:.6f}%".format("#" * int(percent_complete * 20), " " * int(20 - percent_complete * 20), percent_complete * 100, (hits / (hits + misses)) * 100), end="")
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='Cache Benchmark', formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+    parser.add_argument('-c', '--count', type=int, default=100000, help='total number of incrby operations')
+    parser.add_argument('-u', '--uri', type=str, default='redis://localhost:6379', help='Redis server URI')
+    parser.add_argument('-a', '--alpha', type=int, default=1.0, help='alpha value being used for the Zipf distribution')
+    parser.add_argument('-n', '--number', type=int, default=30, help='the number of values to be used in the distribution')
+    parser.add_argument('-d', '--length', type=int, default=10, help='the length of the values to be used in the distribution')
+    parser.add_argument('-p', '--pipeline', type=int, default=0, help='pipeline size')
+
+    args = parser.parse_args()
+    uri = urlparse(args.uri)
+
+    r = redis.StrictRedis(host=uri.hostname, port=uri.port)
+
+    misses = 0
+    hits = 0
+
+    distribution_keys_generator = rand_zipf_generator(args.number, args.alpha, args.count, args.pipeline)
+
+    if args.pipeline == 0:
+        for idx, key in enumerate(distribution_keys_generator):
+            result = r.set(str(key), 'x' * args.length, nx=True)
+            if result:
+                misses += 1
+            else:
+                hits += 1
+            if idx % 50 == 0:
+                update_stats(r, hits, misses, idx, args.count)
+    else:
+        total_count = 0
+        for idx, keys in enumerate(distribution_keys_generator):
+            total_count += len(keys)
+            p = r.pipeline(transaction=False)
+            for key in keys:
+                p.set(str(key), 'x' * args.length, nx=True)
+            responses = p.execute()
+            for resp in responses:
+                if resp:
+                    misses += 1
+                else:
+                    hits += 1
+            if idx % 20 == 0:
+                update_stats(r, hits, misses, total_count, args.count)

tools/requirements.txt

@@ -7,3 +7,4 @@ redis==4.3.4
 requests==2.28.1
 aiocsv==1.2.3
 aiofiles==22.1.0
+numpy==1.24.1