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mirror of https://github.com/CovidBraceletPrj/CovidBracelet.git synced 2024-10-14 18:09:19 +02:00

Fix wrong binary operation in bloom filter and improve infected interval spreading

This commit is contained in:
H1ghBre4k3r 2021-09-23 00:35:29 +02:00 committed by Patrick Rathje
parent 3a2dc985f4
commit 90b756eb3d
2 changed files with 33 additions and 29 deletions

View File

@ -10,6 +10,7 @@ bloom_filter_t* bloom_init(size_t size) {
bloom->size = size;
bloom->data = k_calloc(size, sizeof(uint8_t));
if (!bloom->data) {
bloom->size = 0;
k_free(bloom);
return NULL;
}
@ -26,7 +27,7 @@ void bloom_destroy(bloom_filter_t* bloom) {
void bloom_add_record(bloom_filter_t* bloom, ENIntervalIdentifier* rpi) {
uint8_t* data = bloom->data;
for (int i = 0; i < sizeof(*rpi); i += 2) {
uint32_t hash = rpi->b[i] << 8 & rpi->b[i + 1];
uint32_t hash = (rpi->b[i] << 8) | rpi->b[i + 1];
hash %= bloom->size * 8;
data[hash / 8] |= 1 << (hash % 8);
}
@ -35,7 +36,7 @@ void bloom_add_record(bloom_filter_t* bloom, ENIntervalIdentifier* rpi) {
bool bloom_probably_has_record(bloom_filter_t* bloom, ENIntervalIdentifier* rpi) {
uint8_t* data = bloom->data;
for (int i = 0; i < sizeof(*rpi); i += 2) {
uint32_t hash = rpi->b[i] << 8 & rpi->b[i + 1];
uint32_t hash = (rpi->b[i] << 8) | rpi->b[i + 1];
hash %= bloom->size * 8;
if (!(data[hash / 8] & (1 << (hash % 8)))) {
return false;

View File

@ -145,7 +145,7 @@ void fill_bloom_with_stored_records(bloom_filter_t* bloom) {
// fill bloom filter with records
while (!iterator.finished) {
bloom_add_record(bloom, &iterator.current);
bloom_add_record(bloom, &iterator.current.rolling_proximity_identifier);
ens_records_iterator_next(&iterator);
}
}
@ -180,15 +180,21 @@ int64_t test_bloom_performance(infected_for_period_key_ctx_t* ctx, int count) {
}
}
// Copy infected records to start of array
int amount = 0;
for (int i = 0; i < count; i++) {
amount += ctx[i].infected;
if (ctx[i].infected) {
memcpy(&ctx[amount], &ctx[i], sizeof(ctx[i]));
amount++;
}
}
printk("amount of infected records: %d\n", amount);
int ret = get_number_of_infected_for_multiple_intervals_optimized(ctx, count);
cleanup:
k_free(bloom);
int ret = get_number_of_infected_for_multiple_intervals_dumb(ctx, amount);
// int ret = get_number_of_infected_for_multiple_intervals_simple(ctx, amount);
// int ret = get_number_of_infected_for_multiple_intervals_optimized(ctx, amount);
bloom_destroy(bloom);
return ret;
}
@ -202,19 +208,17 @@ int64_t test_bloom_reverse_performance(infected_for_period_key_ctx_t* ctx, int c
return -1;
}
// Measure bloom creation time
timing_t start_time, end_time;
uint64_t total_cycles;
uint64_t total_ns;
start_time = timing_counter_get();
for (int i = 0; i < count; i++) {
bloom_add_record(bloom, &ctx[i].interval_identifier);
}
end_time = timing_counter_get();
total_cycles = timing_cycles_get(&start_time, &end_time);
total_ns = timing_cycles_to_ns(total_cycles);
printk("\nbloom init took %lld ms\n\n", total_ns / 1000000);
int64_t amount = 0;
@ -244,7 +248,7 @@ int64_t test_bloom_reverse_performance(infected_for_period_key_ctx_t* ctx, int c
}
cleanup:
k_free(bloom);
bloom_destroy(bloom);
return amount;
}
@ -261,21 +265,14 @@ static ENPeriodIdentifierKey infectedPik;
static ENPeriodIdentifierKey dummyPik;
void fill_test_rki_data(infected_for_period_key_ctx_t* infectedIntervals, int count) {
int infectedCount = 50;
int spread = count / infectedCount;
for (int i = 0; i < infectedCount; i++) {
int intervalNumber = (i + 2) * 2;
float range = 1.5;
for (int j = 0; j < spread; j++) {
int offset = (EN_INTERVAL_LENGTH / spread) * j;
infectedIntervals[i * spread + j].infected = 0;
infectedIntervals[i * spread + j].search_start =
(intervalNumber - range) * EN_INTERVAL_LENGTH + offset; // start one and a half intervals before
infectedIntervals[i * spread + j].search_end =
(intervalNumber + range) * EN_INTERVAL_LENGTH + offset; // end one and a half intervals after
en_derive_interval_identifier(&infectedIntervals[i * spread + j].interval_identifier, &infectedPik,
intervalNumber);
}
int totalTime = EN_TEK_ROLLING_PERIOD * EN_INTERVAL_LENGTH;
int stepSize = totalTime / count;
for (int i = 0; i < count; i++) {
int intervalNumber = (i * stepSize) / EN_INTERVAL_LENGTH;
en_derive_interval_identifier(&infectedIntervals[i].interval_identifier, &infectedPik, intervalNumber);
infectedIntervals[i].infected = 0;
infectedIntervals[i].search_start = i < 3 ? 0 : (i - 2) * stepSize;
infectedIntervals[i].search_end = (i + 2) * stepSize;
}
}
@ -308,12 +305,15 @@ void measure_perf(test_func_t func, const char* label, infected_for_period_key_c
printk("\n'%s' took %lld ms\n---------------------------\n", label, total_ns / 1000000);
}
////////////////////
// SETUP DATA //
////////////////////
void setup_test_data() {
en_derive_period_identifier_key(&infectedPik, &infectedPeriodKey);
en_derive_period_identifier_key(&dummyPik, &dummyPeriodKey);
// every 100th interval has an infected record
#define INTERVAL_SPREAD 100
#define INTERVAL_SPREAD 10
for (int i = 0; i < EN_TEK_ROLLING_PERIOD; i++) {
// create infected record
@ -339,10 +339,13 @@ void setup_test_data() {
printk("period %d\n", i);
}
#define INFECTED_INTERVALS_COUNT 500
#define INFECTED_INTERVALS_COUNT 100
// setup our ordered array with infected RPIs
static infected_for_period_key_ctx_t infectedIntervals[INFECTED_INTERVALS_COUNT];
printk("Starting measurements with %d RPIs to seach and an infection rate of every %d. interval\n",
INFECTED_INTERVALS_COUNT, INTERVAL_SPREAD);
// measure_perf(get_number_of_infected_for_multiple_intervals_dumb, "dumb", infectedIntervals,
// INFECTED_INTERVALS_COUNT);
// measure_perf(get_number_of_infected_for_multiple_intervals_simple, "simple", infectedIntervals,