feat(lsm): move keys to db file; idx entries are now constant length

lsm
Jef Roosens 2023-11-11 13:10:14 +01:00
parent a6887d4094
commit 51e4a203e9
Signed by: Jef Roosens
GPG Key ID: B75D4F293C7052DB
2 changed files with 43 additions and 48 deletions

View File

@ -137,12 +137,41 @@ static lsm_error lsm_entry_read_attrs(uint64_t *sum, lsm_entry_handle *handle,
return lsm_error_ok; return lsm_error_ok;
} }
static lsm_error lsm_fseek(FILE *f, uint64_t pos) {
if (fseek(f, pos, SEEK_SET) != 0) {
return lsm_error_failed_io;
}
return lsm_error_ok;
}
/**
* Insert a new entry by reading it from the db file
*/
lsm_error lsm_store_insert_from_db(lsm_store *store, uint64_t pos,
uint64_t idx_file_offset) {
LSM_RES(lsm_fseek(store->db.f, pos));
lsm_str *key;
LSM_RES(lsm_entry_read_str(&key, &store->db.size, store->db.f));
lsm_entry_handle *handle;
LSM_RES(lsm_store_insert(&handle, store, key));
LSM_RES(lsm_fread(&handle->wrapper->entry->data_len, &store->db.size,
store->db.f, sizeof(uint64_t), 1));
LSM_RES(lsm_entry_read_attrs(&store->db.size, handle, store->db.f));
handle->wrapper->entry->idx_file_offset = idx_file_offset;
handle->states = 0;
lsm_entry_close(handle);
return lsm_error_ok;
}
lsm_error lsm_store_load_db(lsm_store *store) { lsm_error lsm_store_load_db(lsm_store *store) {
uint64_t db_dim[2]; uint64_t db_dim[2];
lsm_str *key;
lsm_entry_handle *handle;
bool valid_entry;
rewind(store->idx.f); rewind(store->idx.f);
@ -153,45 +182,15 @@ lsm_error lsm_store_load_db(lsm_store *store) {
for (uint64_t i = 0; i < store->idx.block_count; i++) { for (uint64_t i = 0; i < store->idx.block_count; i++) {
uint64_t idx_file_offset = store->idx.size; uint64_t idx_file_offset = store->idx.size;
LSM_RES(lsm_fread(&valid_entry, &store->idx.size, store->idx.f, LSM_RES(lsm_fread(&db_dim, &store->idx.size, store->idx.f, sizeof(uint64_t),
sizeof(bool), 1)); 2));
if (valid_entry) { // We zero out the length of entries if they're no longer valid
LSM_RES(lsm_entry_read_str(&key, &store->idx.size, store->idx.f)); if (db_dim[1] == 0) {
LSM_RES(lsm_fread(&db_dim, &store->idx.size, store->idx.f, continue;
sizeof(uint64_t), 2));
LSM_RES(lsm_store_insert(&handle, store, key));
// Read attributes from database file
if (fseek(store->db.f, db_dim[0], SEEK_SET) != 0) {
return lsm_error_failed_io;
} }
LSM_RES(lsm_fread(&handle->wrapper->entry->data_len, NULL, store->db.f, LSM_RES(lsm_store_insert_from_db(store, db_dim[0], idx_file_offset));
sizeof(uint64_t), 1));
LSM_RES(lsm_entry_read_attrs(NULL, handle, store->db.f));
handle->wrapper->entry->idx_file_offset = idx_file_offset;
handle->states = 0;
lsm_entry_close(handle);
store->db.size += db_dim[1];
}
// Simply skip the invalid entry
else {
uint64_t key_len;
LSM_RES(lsm_fread(&key_len, &store->idx.size, store->idx.f,
sizeof(uint64_t), 1));
uint64_t remaining = key_len + 2 * sizeof(uint64_t);
if (fseek(store->idx.f, remaining, SEEK_CUR) != 0) {
return lsm_error_failed_io;
}
store->idx.size += remaining;
}
} }
return lsm_error_ok; return lsm_error_ok;

View File

@ -47,6 +47,7 @@ lsm_error lsm_write_db_entry(uint64_t *size, FILE *db_file, lsm_entry *entry,
LSM_RES(lsm_fseek(db_file, pos)); LSM_RES(lsm_fseek(db_file, pos));
LSM_RES(lsm_write_str(size, db_file, entry->key));
LSM_RES(lsm_fwrite(size, db_file, sizeof(uint64_t), 1, &entry->data_len)); LSM_RES(lsm_fwrite(size, db_file, sizeof(uint64_t), 1, &entry->data_len));
LSM_RES(lsm_fwrite(size, db_file, sizeof(uint8_t), 1, &entry->attrs.count)); LSM_RES(lsm_fwrite(size, db_file, sizeof(uint8_t), 1, &entry->attrs.count));
@ -59,16 +60,12 @@ lsm_error lsm_write_db_entry(uint64_t *size, FILE *db_file, lsm_entry *entry,
return lsm_error_ok; return lsm_error_ok;
} }
lsm_error lsm_write_idx_entry(uint64_t *size, FILE *idx_file, lsm_entry *entry, lsm_error lsm_write_idx_entry(uint64_t *size, FILE *idx_file, uint64_t offset,
uint64_t offset, uint64_t len, uint64_t pos) { uint64_t len, uint64_t pos) {
*size = 0; *size = 0;
LSM_RES(lsm_fseek(idx_file, pos)); LSM_RES(lsm_fseek(idx_file, pos));
bool valid_entry_marker = true;
LSM_RES(lsm_fwrite(size, idx_file, sizeof(bool), 1, &valid_entry_marker));
LSM_RES(lsm_write_str(size, idx_file, entry->key));
LSM_RES(lsm_fwrite(size, idx_file, sizeof(uint64_t), 1, &offset)); LSM_RES(lsm_fwrite(size, idx_file, sizeof(uint64_t), 1, &offset));
LSM_RES(lsm_fwrite(size, idx_file, sizeof(uint64_t), 1, &len)); LSM_RES(lsm_fwrite(size, idx_file, sizeof(uint64_t), 1, &len));
@ -99,9 +96,8 @@ lsm_error lsm_entry_disk_insert(lsm_entry_handle *handle) {
uint64_t idx_entry_index = store->idx.size; uint64_t idx_entry_index = store->idx.size;
uint64_t idx_entry_size; uint64_t idx_entry_size;
res = res = lsm_write_idx_entry(&idx_entry_size, store->idx.f, db_entry_index,
lsm_write_idx_entry(&idx_entry_size, store->idx.f, handle->wrapper->entry, db_entry_size, store->idx.size);
db_entry_index, db_entry_size, store->idx.size);
if (res == lsm_error_ok) { if (res == lsm_error_ok) {
// Update the counter at the beginning of the file // Update the counter at the beginning of the file