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Added sparse btree tests, fixed found bugs (grow/shrink bisect)

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- After a B-tree split, when we're append pending attributes, it's
  possible for the id chosen for bisection to be itself modified by
  pending grows/shrinks. This needs to be accounted for in the two
  passes for the two children.

But this means our tests are working.
This commit is contained in:
Christopher Haster
2023-03-08 02:52:34 -06:00
parent 0a3c6b39c1
commit ce18bec66d
3 changed files with 421 additions and 49 deletions
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tests/test_btree.toml
+350 -2
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@@ -398,15 +398,26 @@ code = '''
// add to btree
lfsr_btree_push(&lfs, &btree, id, LFSR_TAG_INLINED, 1,
&alphas[i], 1) => 0;
&alphas[i % 26], 1) => 0;
// add to sim
memcpy(&sim[id+1], &sim[id], sim_size-id);
sim[id] = alphas[i];
sim[id] = alphas[i % 26];
sim_size += 1;
}
// check that btree matches sim
printf("expd: [");
bool first = true;
for (lfs_size_t i = 0; i < N; i++) {
if (!first) {
printf(", ");
}
first = false;
printf("%c", sim[i]);
}
printf("]\n");
assert(btree.weight == N);
uint8_t buffer[4];
@@ -433,3 +444,340 @@ code = '''
}
'''
[cases.test_btree_sparse]
defines.N = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
defines.W = 5
in = 'lfs.c'
code = '''
lfs_t lfs;
lfs_init(&lfs, cfg) => 0;
// create free lookahead
memset(lfs.free.buffer, 0, lfs.cfg->lookahead_size);
lfs.free.off = 0;
lfs.free.size = lfs_min(8*lfs.cfg->lookahead_size,
lfs.cfg->block_count);
lfs.free.i = 0;
lfs_alloc_ack(&lfs);
// create a tree with N elements
lfsr_btree_t btree = LFSR_BTREE_NULL;
const char *alphas = "abcdefghijklmnopqrstuvwxyz";
for (lfs_size_t i = 0; i < N; i++) {
lfsr_btree_push(&lfs, &btree, i*W, LFSR_TAG_INLINED, W,
&alphas[i % 26], 1) => 0;
}
// check that the elements are in the tree
uint8_t buffer[4];
lfsr_tag_t tag_;
lfs_size_t id_;
lfs_size_t weight_;
for (lfs_size_t i = 0; i < N; i++) {
lfsr_btree_get(&lfs, &btree, i*W+W-1,
&tag_, &id_, &weight_,
buffer, 4) => 1;
assert(tag_ == LFSR_TAG_INLINED);
assert(id_ == i*W+W-1);
assert(weight_ == W);
assert(memcmp(buffer, &alphas[i % 26], 1) == 0);
}
// and check that we can't lookup elements that aren't in the tree
lfsr_btree_get(&lfs, &btree, N*W,
&tag_, &id_, &weight_,
buffer, 4) => LFS_ERR_NOENT;
'''
[cases.test_btree_sparse_fuzz]
defines.N = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
defines.W = 5
defines.ITER = 10
in = 'lfs.c'
code = '''
const char *alphas = "abcdefghijklmnopqrstuvwxyz";
// iterate through severals seeds that we can reproduce easily
for (uint32_t seed = 1; seed < ITER+1; seed++) {
// create lfs here since we need to reset each iteration, we're
// space constrained and we can't expect gc to work at this point
lfs_t lfs;
lfs_init(&lfs, cfg) => 0;
// create free lookahead
memset(lfs.free.buffer, 0, lfs.cfg->lookahead_size);
lfs.free.off = 0;
lfs.free.size = lfs_min(8*lfs.cfg->lookahead_size,
lfs.cfg->block_count);
lfs.free.i = 0;
lfs_alloc_ack(&lfs);
// create a btree
lfsr_btree_t btree = LFSR_BTREE_NULL;
// set up a simulation to compare against
//
// fun fact this is slower than our actual tree! unfun fact this is
// starting to be a problem...
char *sim = malloc(N);
lfs_size_t *sim_weights = malloc(N*sizeof(lfs_size_t));
lfs_size_t sim_size = 0;
memset(sim, 0, N);
memset(sim_weights, 0, N*sizeof(lfs_size_t));
uint32_t prng = seed;
for (lfs_size_t i = 0; i < N; i++) {
// choose a pseudo-random id
lfs_size_t id = TEST_PRNG(&prng) % (sim_size+1);
// choose a pseudo-random weight
lfs_size_t weight = 1 + (TEST_PRNG(&prng) % W);
// calculate actual id in btree space
lfs_size_t weighted_id = 0;
for (lfs_size_t j = 0; j < id; j++) {
weighted_id += sim_weights[j];
}
// add to btree
lfsr_btree_push(&lfs, &btree, weighted_id, LFSR_TAG_INLINED, weight,
&alphas[i % 26], 1) => 0;
// add to sim
memcpy(&sim[id+1], &sim[id], sim_size-id);
memcpy(&sim_weights[id+1], &sim_weights[id],
(sim_size-id)*sizeof(lfs_size_t));
sim[id] = alphas[i % 26];
sim_weights[id] = weight;
sim_size += 1;
}
// check that btree matches sim
printf("expd: [");
bool first = true;
for (lfs_size_t i = 0; i < N; i++) {
// calculate actual id in btree space
lfs_size_t weighted_id = 0;
for (lfs_size_t j = 0; j < i; j++) {
weighted_id += sim_weights[j];
}
if (!first) {
printf(", ");
}
first = false;
printf("%dw%d=%c", weighted_id+sim_weights[i]-1,
sim_weights[i], sim[i]);
}
printf("]\n");
lfs_size_t total_weight = 0;
for (lfs_size_t j = 0; j < N; j++) {
total_weight += sim_weights[j];
}
assert(btree.weight == total_weight);
uint8_t buffer[4];
lfsr_tag_t tag_;
lfs_size_t id_;
lfs_size_t weight_;
for (lfs_size_t i = 0; i < N; i++) {
// calculate actual id in btree space
lfs_size_t weighted_id = 0;
for (lfs_size_t j = 0; j < i; j++) {
weighted_id += sim_weights[j];
}
lfsr_btree_get(&lfs, &btree, weighted_id+sim_weights[i]-1,
&tag_, &id_, &weight_,
buffer, 4) => 1;
assert(tag_ == LFSR_TAG_INLINED);
assert(id_ == weighted_id+sim_weights[i]-1);
assert(weight_ == sim_weights[i]);
assert(memcmp(buffer, &sim[i], 1) == 0);
}
// and no extra elements
lfsr_btree_get(&lfs, &btree, total_weight,
&tag_, &id_, &weight_,
buffer, 4) => LFS_ERR_NOENT;
// clean up sim
free(sim);
}
'''
[cases.test_btree_traverse]
defines.N = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
defines.W = 5
in = 'lfs.c'
code = '''
lfs_t lfs;
lfs_init(&lfs, cfg) => 0;
// create free lookahead
memset(lfs.free.buffer, 0, lfs.cfg->lookahead_size);
lfs.free.off = 0;
lfs.free.size = lfs_min(8*lfs.cfg->lookahead_size,
lfs.cfg->block_count);
lfs.free.i = 0;
lfs_alloc_ack(&lfs);
// create a tree with N elements
lfsr_btree_t btree = LFSR_BTREE_NULL;
const char *alphas = "abcdefghijklmnopqrstuvwxyz";
for (lfs_size_t i = 0; i < N; i++) {
lfsr_btree_push(&lfs, &btree, i*W, LFSR_TAG_INLINED, W,
&alphas[i % 26], 1) => 0;
}
// traverse the elements in the tree
uint8_t buffer[4];
lfs_size_t id_ = -1;
lfsr_tag_t tag_;
lfs_size_t weight_;
for (lfs_size_t i = 0; i < N; i++) {
lfsr_btree_get(&lfs, &btree, id_+1,
&tag_, &id_, &weight_,
buffer, 4) => 1;
assert(tag_ == LFSR_TAG_INLINED);
assert(id_ == i*W+W-1);
assert(weight_ == W);
assert(memcmp(buffer, &alphas[i % 26], 1) == 0);
}
// and check that we can't lookup elements that aren't in the tree
lfsr_btree_get(&lfs, &btree, id_+1,
&tag_, &id_, &weight_,
buffer, 4) => LFS_ERR_NOENT;
'''
[cases.test_btree_traverse_fuzz]
defines.N = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
defines.W = 5
defines.ITER = 10
in = 'lfs.c'
code = '''
const char *alphas = "abcdefghijklmnopqrstuvwxyz";
// iterate through severals seeds that we can reproduce easily
for (uint32_t seed = 1; seed < ITER+1; seed++) {
// create lfs here since we need to reset each iteration, we're
// space constrained and we can't expect gc to work at this point
lfs_t lfs;
lfs_init(&lfs, cfg) => 0;
// create free lookahead
memset(lfs.free.buffer, 0, lfs.cfg->lookahead_size);
lfs.free.off = 0;
lfs.free.size = lfs_min(8*lfs.cfg->lookahead_size,
lfs.cfg->block_count);
lfs.free.i = 0;
lfs_alloc_ack(&lfs);
// create a btree
lfsr_btree_t btree = LFSR_BTREE_NULL;
// set up a simulation to compare against
//
// fun fact this is slower than our actual tree! unfun fact this is
// starting to be a problem...
char *sim = malloc(N);
lfs_size_t *sim_weights = malloc(N*sizeof(lfs_size_t));
lfs_size_t sim_size = 0;
memset(sim, 0, N);
memset(sim_weights, 0, N*sizeof(lfs_size_t));
uint32_t prng = seed;
for (lfs_size_t i = 0; i < N; i++) {
// choose a pseudo-random id
lfs_size_t id = TEST_PRNG(&prng) % (sim_size+1);
// choose a pseudo-random weight
lfs_size_t weight = 1 + (TEST_PRNG(&prng) % W);
// calculate actual id in btree space
lfs_size_t weighted_id = 0;
for (lfs_size_t j = 0; j < id; j++) {
weighted_id += sim_weights[j];
}
// add to btree
lfsr_btree_push(&lfs, &btree, weighted_id, LFSR_TAG_INLINED, weight,
&alphas[i % 26], 1) => 0;
// add to sim
memcpy(&sim[id+1], &sim[id], sim_size-id);
memcpy(&sim_weights[id+1], &sim_weights[id],
(sim_size-id)*sizeof(lfs_size_t));
sim[id] = alphas[i % 26];
sim_weights[id] = weight;
sim_size += 1;
}
// check that btree matches sim
printf("expd: [");
bool first = true;
for (lfs_size_t i = 0; i < N; i++) {
// calculate actual id in btree space
lfs_size_t weighted_id = 0;
for (lfs_size_t j = 0; j < i; j++) {
weighted_id += sim_weights[j];
}
if (!first) {
printf(", ");
}
first = false;
printf("%dw%d=%c", weighted_id+sim_weights[i]-1,
sim_weights[i], sim[i]);
}
printf("]\n");
lfs_size_t total_weight = 0;
for (lfs_size_t j = 0; j < N; j++) {
total_weight += sim_weights[j];
}
assert(btree.weight == total_weight);
uint8_t buffer[4];
lfs_size_t id_ = -1;
lfsr_tag_t tag_;
lfs_size_t weight_;
for (lfs_size_t i = 0; i < N; i++) {
// calculate actual id in btree space
lfs_size_t weighted_id = 0;
for (lfs_size_t j = 0; j < i; j++) {
weighted_id += sim_weights[j];
}
lfsr_btree_get(&lfs, &btree, id_+1,
&tag_, &id_, &weight_,
buffer, 4) => 1;
assert(tag_ == LFSR_TAG_INLINED);
assert(id_ == weighted_id+sim_weights[i]-1);
assert(weight_ == sim_weights[i]);
assert(memcmp(buffer, &sim[i], 1) == 0);
}
// and no extra elements
lfsr_btree_get(&lfs, &btree, id_+1,
&tag_, &id_, &weight_,
buffer, 4) => LFS_ERR_NOENT;
// clean up sim
free(sim);
}
'''
# [cases.test_btree_update]
# [cases.test_btree_update_fuzz]
# [cases.test_btree_update_sparse]
# [cases.test_btree_update_sparse_fuzz]
# [cases.test_btree_update_traverse]
# [cases.test_btree_update_traverse_fuzz]
# [cases.test_btree_pop]
# [cases.test_btree_pop_fuzz]
# [cases.test_btree_split]
# [cases.test_btree_split_fuzz]
# [cases.test_btree_general_fuzz]
# TODO also test copy-on-write!