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Hash-based PG distribution experiments

trace-sqes
Vitaliy Filippov 1 year ago
parent
commit
3a4279adbf
  1. 2
      Makefile
  2. 304
      test.cpp

2
Makefile

@ -65,6 +65,6 @@ libfio_sec_osd.so: fio_sec_osd.cpp osd_ops.h rw_blocking.o
test_blockstore: ./libblockstore.so test_blockstore.cpp
g++ $(CXXFLAGS) -o test_blockstore test_blockstore.cpp ./libblockstore.so -ltcmalloc_minimal -luring
test: test.cpp osd_peering_pg.o
g++ $(CXXFLAGS) -o test test.cpp osd_peering_pg.o -luring
g++ $(CXXFLAGS) -o test test.cpp osd_peering_pg.o -luring -lm
test_allocator: test_allocator.cpp allocator.o
g++ $(CXXFLAGS) -o test_allocator test_allocator.cpp allocator.o

304
test.cpp

@ -13,6 +13,7 @@
#include <assert.h>
#include <stdio.h>
#include <liburing.h>
#include <math.h>
#include <sys/socket.h>
#include <sys/epoll.h>
@ -26,6 +27,7 @@
#include "blockstore.h"
#include "blockstore_impl.h"
#include "osd_peering_pg.h"
//#include "cpp-btree/btree_map.h"
static int setup_context(unsigned entries, struct io_uring *ring)
@ -60,24 +62,6 @@ static void test_write(struct io_uring *ring, int fd)
free(buf);
}
class obj_ver_hash
{
public:
size_t operator()(const obj_ver_id &s) const
{
size_t seed = 0;
spp::hash_combine(seed, s.oid.inode);
spp::hash_combine(seed, s.oid.stripe);
spp::hash_combine(seed, s.version);
return seed;
}
};
inline bool operator == (const obj_ver_id & a, const obj_ver_id & b)
{
return a.oid == b.oid && a.version == b.version;
}
int main00(int argc, char *argv[])
{
// queue with random removal: vector is best :D
@ -169,9 +153,9 @@ int main0(int argc, char *argv[])
// btree_map 5M entries monotone -> 0.458s, random -> 5.429s
// absl::btree_map 5M entries random -> 5.09s
// sparse_hash_map 5M entries -> 2.193s, random -> 2.586s
//btree::btree_map<obj_ver_id, dirty_entry> dirty_db;
btree::btree_map<obj_ver_id, dirty_entry> dirty_db;
//std::map<obj_ver_id, dirty_entry> dirty_db;
spp::sparse_hash_map<obj_ver_id, dirty_entry, obj_ver_hash> dirty_db;
//spp::sparse_hash_map<obj_ver_id, dirty_entry, obj_ver_hash> dirty_db;
for (int i = 0; i < 5000000; i++)
{
dirty_db[(obj_ver_id){
@ -336,49 +320,253 @@ int main04(int argc, char *argv[])
return 0;
}
uint64_t jumphash(uint64_t key, int count)
{
uint64_t b = 0;
uint64_t seed = key;
for (int j = 1; j < count; j++)
{
seed = 2862933555777941757ull*seed + 3037000493ull; // LCPRNG
if (seed < (UINT64_MAX / (j+1)))
{
b = j;
}
}
return b;
}
void jumphash_prepare(int count, uint64_t *out_weights, uint64_t *in_weights)
{
if (count <= 0)
{
return;
}
uint64_t total_weight = in_weights[0];
out_weights[0] = UINT64_MAX;
for (int j = 1; j < count; j++)
{
total_weight += in_weights[j];
out_weights[j] = UINT64_MAX / total_weight * in_weights[j];
}
}
uint64_t jumphash_weights(uint64_t key, int count, uint64_t *prepared_weights)
{
uint64_t b = 0;
uint64_t seed = key;
for (int j = 1; j < count; j++)
{
seed = 2862933555777941757ull*seed + 3037000493ull; // LCPRNG
if (seed < prepared_weights[j])
{
b = j;
}
}
return b;
}
void jumphash3(uint64_t key, int count, uint64_t *weights, uint64_t *r)
{
r[0] = 0;
r[1] = 1;
r[2] = 2;
uint64_t total_weight = weights[0]+weights[1]+weights[2];
uint64_t seed = key;
for (int j = 3; j < count; j++)
{
seed = 2862933555777941757ull*seed + 3037000493ull; // LCPRNG
total_weight += weights[j];
if (seed < UINT64_MAX*1.0*weights[j]/total_weight)
r[0] = j;
else
{
seed = 2862933555777941757ull*seed + 3037000493ull; // LCPRNG
if (seed < UINT64_MAX*1.0*weights[j]/total_weight)
r[1] = j;
else
{
seed = 2862933555777941757ull*seed + 3037000493ull; // LCPRNG
if (seed < UINT64_MAX*1.0*weights[j]/total_weight)
r[2] = j;
}
}
}
}
uint64_t crush(uint64_t key, int count, uint64_t *weights)
{
uint64_t b = 0;
uint64_t seed = 0;
uint64_t max = 0;
for (int j = 0; j < count; j++)
{
seed = (key + 0xc6a4a7935bd1e995 + (seed << 6) + (seed >> 2));
seed ^= (j + 0xc6a4a7935bd1e995 + (seed << 6) + (seed >> 2));
seed = 2862933555777941757ull*seed + 3037000493ull; // LCPRNG
seed = -log(((double)seed) / (1ul << 32) / (1ul << 32)) * weights[j];
if (seed > max)
{
max = seed;
b = j;
}
}
return b;
}
void crush3(uint64_t key, int count, uint64_t *weights, uint64_t *r, uint64_t total_weight)
{
uint64_t seed = 0;
uint64_t max = 0;
for (int k1 = 0; k1 < count; k1++)
{
for (int k2 = k1+1; k2 < count; k2++)
{
if (k2 == k1)
{
continue;
}
for (int k3 = k2+1; k3 < count; k3++)
{
if (k3 == k1 || k3 == k2)
{
continue;
}
seed = (key + 0xc6a4a7935bd1e995 + (seed << 6) + (seed >> 2));
seed ^= (k1 + 0xc6a4a7935bd1e995 + (seed << 6) + (seed >> 2));
seed ^= (k2 + 0xc6a4a7935bd1e995 + (seed << 6) + (seed >> 2));
seed ^= (k3 + 0xc6a4a7935bd1e995 + (seed << 6) + (seed >> 2));
seed = 2862933555777941757ull*seed + 3037000493ull; // LCPRNG
//seed = ((double)seed) / (1ul << 32) / (1ul << 32) * (weights[k1] + weights[k2] + weights[k3]);
seed = ((double)seed) / (1ul << 32) / (1ul << 32) * (1 -
(1 - 1.0*weights[k1]/total_weight)*
(1 - 1.0*weights[k2]/total_weight)*
(1 - 1.0*weights[k3]/total_weight)
) * UINT64_MAX;
if (seed > max)
{
r[0] = k1;
r[1] = k2;
r[2] = k3;
max = seed;
}
}
}
}
}
int main(int argc, char *argv[])
{
timeval fill_start, fill_end, filter_end;
spp::sparse_hash_map<object_id, clean_entry> clean_db;
//std::map<object_id, clean_entry> clean_db;
//btree::btree_map<object_id, clean_entry> clean_db;
gettimeofday(&fill_start, NULL);
printf("filling\n");
uint64_t total = 1024*1024*8*4;
clean_db.resize(total);
for (uint64_t i = 0; i < total; i++)
int host_count = 6;
uint64_t host_weights[] = {
34609*3,
34931*3,
35850+36387+35859,
36387,
36387*2,
36387,
};
/*int osd_count[] = { 3, 3, 3, 1, 2 };
uint64_t osd_weights[][3] = {
{ 34609, 34609, 34609 },
{ 34931, 34931, 34931 },
{ 35850, 36387, 35859 },
{ 36387 },
{ 36387, 36387 },
};*/
uint64_t total_weight = 0;
for (int i = 0; i < host_count; i++)
{
clean_db[(object_id){
.inode = 1,
//.stripe = (i << STRIPE_SHIFT),
.stripe = (((367*i) % total) << STRIPE_SHIFT),
}] = (clean_entry){
.version = 1,
.location = i << DEFAULT_ORDER,
};
total_weight += host_weights[i];
}
uint64_t host_weights_prepared[host_count];
jumphash_prepare(host_count, host_weights_prepared, host_weights);
uint64_t total_pgs[host_count] = { 0 };
int pg_count = 256;
double uniformity[pg_count] = { 0 };
for (uint64_t pg = 1; pg <= pg_count; pg++)
{
uint64_t r[3];
/*
// Select first host
//r[0] = jumphash_weights(pg, host_count, host_weights_prepared);
r[0] = crush(pg, host_count, host_weights);
// Select second host
uint64_t seed = pg;
r[1] = r[0];
while (r[1] == r[0])
{
seed = 2862933555777941757ull*seed + 3037000493ull; // LCPRNG
//r[1] = jumphash_weights(seed, host_count, host_weights_prepared);
r[1] = crush(seed, host_count, host_weights);
}
// Select third host
seed = pg;
r[2] = r[0];
while (r[2] == r[0] || r[2] == r[1])
{
seed = 2862933555777941757ull*seed + 3037000493ull; // LCPRNG
//r[2] = jumphash_weights(seed, host_count, host_weights_prepared);
r[2] = crush(seed, host_count, host_weights);
}
*/
/*
// Select second host
uint64_t host_weights1[host_count];
for (int i = 0; i < r[0]; i++)
host_weights1[i] = host_weights[i];
for (int i = r[0]+1; i < host_count; i++)
host_weights1[i-1] = host_weights[i];
r[1] = crush(pg, host_count-1, host_weights1);
// Select third host
for (int i = r[1]+1; i < host_count-1; i++)
host_weights1[i-1] = host_weights[i];
r[2] = crush(pg, host_count-2, host_weights1);
// Transform numbers
r[2] = r[2] >= r[1] ? 1+r[2] : r[2];
r[2] = r[2] >= r[0] ? 1+r[2] : r[2];
r[1] = r[1] >= r[0] ? 1+r[1] : r[1];
*/
crush3(pg, host_count, host_weights, r, total_weight);
uint64_t shift = (2862933555777941757ull*pg + 3037000493ull) % host_count;
if (shift == 1)
{
uint64_t tmp;
tmp = r[0];
r[0] = r[1];
r[1] = r[2];
r[2] = tmp;
}
else if (shift == 2)
{
uint64_t tmp;
tmp = r[0];
r[0] = r[2];
r[2] = r[1];
r[1] = tmp;
}
total_pgs[r[0]]++;
total_pgs[r[1]]++;
total_pgs[r[2]]++;
double u = 0;
for (int i = 0; i < host_count; i++)
{
double d = abs(1 - total_pgs[i]/3.0/pg * total_weight/host_weights[i]);
u += d;
}
uniformity[pg-1] = u/host_count;
printf("pg %lu: hosts %lu, %lu, %lu ; avg deviation = %.2f\n", pg, r[0], r[1], r[2], u/host_count);
}
gettimeofday(&fill_end, NULL);
// no resize():
// spp = 17.87s (seq), 41.81s (rand), 3.29s (seq+resize), 8.3s (rand+resize), ~1.3G RAM in all cases
// std::unordered_map = 6.14 sec, ~2.3G RAM
// std::map = 13 sec (seq), 5.54 sec (rand), ~2.5G RAM
// cpp-btree = 2.47 sec (seq) ~1.2G RAM, 20.6 sec (pseudo-random 367*i % total) ~1.5G RAM
printf("filled %.2f sec\n", (fill_end.tv_sec - fill_start.tv_sec) + (fill_end.tv_usec - fill_start.tv_usec) / 1000000.0);
for (int pg = 0; pg < 100; pg++)
printf("total PGs: ");
for (int i = 0; i < host_count; i++)
{
obj_ver_id* buf1 = (obj_ver_id*)malloc(sizeof(obj_ver_id) * ((total+99)/100));
int j = 0;
for (auto it: clean_db)
if ((it.first % 100) == pg)
buf1[j++] = { .oid = it.first, .version = it.second.version };
free(buf1);
printf("filtered %d\n", j);
printf(i > 0 ? ", %lu (%.2f)" : "%lu (%.2f)", total_pgs[i], total_pgs[i]/3.0/pg_count * total_weight/host_weights[i]);
}
gettimeofday(&filter_end, NULL);
// spp = 42.15 sec / 60 sec (rand)
// std::unordered_map = 43.7 sec
// std::map = 156.13 sec
// cpp-btree = 21.87 sec (seq), 44.33 sec (rand)
printf("100 times filter %.2f sec\n", (filter_end.tv_sec - fill_end.tv_sec) + (filter_end.tv_usec - fill_end.tv_usec) / 1000000.0);
printf("\n");
return 0;
}
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