1 files changed, 0 insertions, 158 deletions
diff --git a/examples/redis-unstable/utils/lru/lfu-simulation.c b/examples/redis-unstable/utils/lru/lfu-simulation.c
deleted file mode 100644
index 60105e5..0000000
--- a/examples/redis-unstable/utils/lru/lfu-simulation.c
+++ /dev/null
@@ -1,158 +0,0 @@
-#include <stdio.h>
-#include <time.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-int decr_every = 1;
-int keyspace_size = 1000000;
-time_t switch_after = 30; /* Switch access pattern after N seconds. */
-
-struct entry {
-    /* Field that the LFU Redis implementation will have (we have
-     * 24 bits of total space in the object->lru field). */
-    uint8_t counter;    /* Logarithmic counter. */
-    uint16_t decrtime;  /* (Reduced precision) time of last decrement. */
-
-    /* Fields only useful for visualization. */
-    uint64_t hits;      /* Number of real accesses. */
-    time_t ctime;       /* Key creation time. */
-};
-
-#define to_16bit_minutes(x) ((x/60) & 65535)
-#define LFU_INIT_VAL 5
-
-/* Compute the difference in minutes between two 16 bit minutes times
- * obtained with to_16bit_minutes(). Since they can wrap around if
- * we detect the overflow we account for it as if the counter wrapped
- * a single time. */
-uint16_t minutes_diff(uint16_t now, uint16_t prev) {
-    if (now >= prev) return now-prev;
-    return 65535-prev+now;
-}
-
-/* Increment a counter logarithmically: the greatest is its value, the
- * less likely is that the counter is really incremented.
- * The maximum value of the counter is saturated at 255. */
-uint8_t log_incr(uint8_t counter) {
-    if (counter == 255) return counter;
-    double r = (double)rand()/RAND_MAX;
-    double baseval = counter-LFU_INIT_VAL;
-    if (baseval < 0) baseval = 0;
-    double limit = 1.0/(baseval*10+1);
-    if (r < limit) counter++;
-    return counter;
-}
-
-/* Simulate an access to an entry. */
-void access_entry(struct entry *e) {
-    e->counter = log_incr(e->counter);
-    e->hits++;
-}
-
-/* Return the entry LFU value and as a side effect decrement the
- * entry value if the decrement time was reached. */
-uint8_t scan_entry(struct entry *e) {
-    if (minutes_diff(to_16bit_minutes(time(NULL)),e->decrtime)
-        >= decr_every)
-    {
-        if (e->counter) {
-            if (e->counter > LFU_INIT_VAL*2) {
-                e->counter /= 2;
-            } else {
-                e->counter--;
-            }
-        }
-        e->decrtime = to_16bit_minutes(time(NULL));
-    }
-    return e->counter;
-}
-
-/* Print the entry info. */
-void show_entry(long pos, struct entry *e) {
-    char *tag = "normal       ";
-
-    if (pos >= 10 && pos <= 14) tag = "new no access";
-    if (pos >= 15 && pos <= 19) tag = "new accessed ";
-    if (pos >= keyspace_size -5) tag= "old no access";
-
-    printf("%ld] <%s> frequency:%d decrtime:%d [%lu hits | age:%ld sec]\n",
-        pos, tag, e->counter, e->decrtime, (unsigned long)e->hits,
-            time(NULL) - e->ctime);
-}
-
-int main(void) {
-    time_t start = time(NULL);
-    time_t new_entry_time = start;
-    time_t display_time = start;
-    struct entry *entries = malloc(sizeof(*entries)*keyspace_size);
-    long j;
-
-    /* Initialize. */
-    for (j = 0; j < keyspace_size; j++) {
-        entries[j].counter = LFU_INIT_VAL;
-        entries[j].decrtime = to_16bit_minutes(start);
-        entries[j].hits = 0;
-        entries[j].ctime = time(NULL);
-    }
-
-    while(1) {
-        time_t now = time(NULL);
-        long idx;
-
-        /* Scan N random entries (simulates the eviction under maxmemory). */
-        for (j = 0; j < 3; j++) {
-            scan_entry(entries+(rand()%keyspace_size));
-        }
-
-        /* Access a random entry: use a power-law access pattern up to
-         * 'switch_after' seconds. Then revert to flat access pattern. */
-        if (now-start < switch_after) {
-            /* Power law. */
-            idx = 1;
-            while((rand() % 21) != 0 && idx < keyspace_size) idx *= 2;
-            if (idx > keyspace_size) idx = keyspace_size;
-            idx = rand() % idx;
-        } else {
-            /* Flat. */
-            idx = rand() % keyspace_size;
-        }
-
-        /* Never access entries between position 10 and 14, so that
-         * we simulate what happens to new entries that are never
-         * accessed VS new entries which are accessed in positions
-         * 15-19.
-         *
-         * Also never access last 5 entry, so that we have keys which
-         * are never recreated (old), and never accessed. */
-        if ((idx < 10 || idx > 14) && (idx < keyspace_size-5))
-            access_entry(entries+idx);
-
-        /* Simulate the addition of new entries at positions between
-         * 10 and 19, a random one every 10 seconds. */
-        if (new_entry_time <= now) {
-            idx = 10+(rand()%10);
-            entries[idx].counter = LFU_INIT_VAL;
-            entries[idx].decrtime = to_16bit_minutes(time(NULL));
-            entries[idx].hits = 0;
-            entries[idx].ctime = time(NULL);
-            new_entry_time = now+10;
-        }
-
-        /* Show the first 20 entries and the last 20 entries. */
-        if (display_time != now) {
-            printf("=============================\n");
-            printf("Current minutes time: %d\n", (int)to_16bit_minutes(now));
-            printf("Access method: %s\n",
-                (now-start < switch_after) ? "power-law" : "flat");
-
-            for (j = 0; j < 20; j++)
-                show_entry(j,entries+j);
-
-            for (j = keyspace_size-20; j < keyspace_size; j++)
-                show_entry(j,entries+j);
-            display_time = now;
-        }
-    }
-    return 0;
-}
-