Outdated comments, replace COUNTER_INIT_VAL with LFU_INIT_VAL, fix typo (#10888)

`COUNTER_INIT_VAL` doesn't exist in the code anymore so we can replace it with `LFU_INIT_VAL` entries
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Vlad 2022-06-21 07:14:31 +02:00 committed by GitHub
parent 091701f363
commit a3fdc9cd82
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2 changed files with 10 additions and 10 deletions

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@ -266,14 +266,14 @@ void evictionPoolPopulate(int dbid, dict *sampledict, dict *keydict, struct evic
* has a low value.
*
* New keys don't start at zero, in order to have the ability to collect
* some accesses before being trashed away, so they start at COUNTER_INIT_VAL.
* The logarithmic increment performed on LOG_C takes care of COUNTER_INIT_VAL
* when incrementing the key, so that keys starting at COUNTER_INIT_VAL
* some accesses before being trashed away, so they start at LFU_INIT_VAL.
* The logarithmic increment performed on LOG_C takes care of LFU_INIT_VAL
* when incrementing the key, so that keys starting at LFU_INIT_VAL
* (or having a smaller value) have a very high chance of being incremented
* on access.
*
* During decrement, the value of the logarithmic counter is halved if
* its current value is greater than two times the COUNTER_INIT_VAL, otherwise
* its current value is greater than two times the LFU_INIT_VAL, otherwise
* it is just decremented by one.
* --------------------------------------------------------------------------*/
@ -295,7 +295,7 @@ unsigned long LFUTimeElapsed(unsigned long ldt) {
}
/* Logarithmically increment a counter. The greater is the current counter value
* the less likely is that it gets really implemented. Saturate it at 255. */
* the less likely is that it gets really incremented. Saturate it at 255. */
uint8_t LFULogIncr(uint8_t counter) {
if (counter == 255) return 255;
double r = (double)rand()/RAND_MAX;

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@ -19,7 +19,7 @@ struct entry {
};
#define to_16bit_minutes(x) ((x/60) & 65535)
#define COUNTER_INIT_VAL 5
#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
@ -36,7 +36,7 @@ uint16_t minutes_diff(uint16_t now, uint16_t prev) {
uint8_t log_incr(uint8_t counter) {
if (counter == 255) return counter;
double r = (double)rand()/RAND_MAX;
double baseval = counter-COUNTER_INIT_VAL;
double baseval = counter-LFU_INIT_VAL;
if (baseval < 0) baseval = 0;
double limit = 1.0/(baseval*10+1);
if (r < limit) counter++;
@ -56,7 +56,7 @@ uint8_t scan_entry(struct entry *e) {
>= decr_every)
{
if (e->counter) {
if (e->counter > COUNTER_INIT_VAL*2) {
if (e->counter > LFU_INIT_VAL*2) {
e->counter /= 2;
} else {
e->counter--;
@ -89,7 +89,7 @@ int main(void) {
/* Initialize. */
for (j = 0; j < keyspace_size; j++) {
entries[j].counter = COUNTER_INIT_VAL;
entries[j].counter = LFU_INIT_VAL;
entries[j].decrtime = to_16bit_minutes(start);
entries[j].hits = 0;
entries[j].ctime = time(NULL);
@ -131,7 +131,7 @@ int main(void) {
* 10 and 19, a random one every 10 seconds. */
if (new_entry_time <= now) {
idx = 10+(rand()%10);
entries[idx].counter = COUNTER_INIT_VAL;
entries[idx].counter = LFU_INIT_VAL;
entries[idx].decrtime = to_16bit_minutes(time(NULL));
entries[idx].hits = 0;
entries[idx].ctime = time(NULL);