[For Performance Branch] Bloom filter in PlainTableIterator::Seek() - Update 1

Summary:
Address @haobo's comments in D14277

Test Plan: ./indexed_table_db_test

Reviewers: haobo

CC:

Task ID: #

Blame Rev:
This commit is contained in:
Siying Dong 2013-11-21 23:33:45 -08:00
parent 718488abc5
commit dfa1460d88
3 changed files with 10 additions and 8 deletions

View File

@ -48,8 +48,8 @@ public:
~PlainTableFactory() {
}
// user_key_size is the length of the user key. key_prefix_len is the
// length of the prefix used for im-memory indexes. bloom_num_bits is
// number of bits is used for bloom filer per key. hash_table_ratio is
// length of the prefix used for in-memory indexes. bloom_num_bits is
// number of bits used for bloom filer per key. hash_table_ratio is
// the desired ultilization of the hash table used for prefix hashing.
// hash_table_ratio = number of prefixes / #buckets in the hash table
PlainTableFactory(int user_key_size, int key_prefix_len,

View File

@ -162,10 +162,10 @@ Status PlainTableReader::PopulateIndex(uint64_t file_size) {
// Make the hash table 3/5 full
std::vector<Slice> filter_entries(0); // for creating bloom filter;
if (filter_policy_ != nullptr) {
filter_entries.resize(tmp_index.size());
filter_entries.reserve(tmp_index.size());
}
double hash_table_size_multipier =
(hash_table_ratio_ < 1.0) ? 1.0 : 1.0 / hash_table_ratio_;
(hash_table_ratio_ > 1.0) ? 1.0 : 1.0 / hash_table_ratio_;
hash_table_size_ = tmp_index.size() * hash_table_size_multipier + 1;
hash_table_ = new char[GetHashTableRecordLen() * hash_table_size_];
for (int i = 0; i < hash_table_size_; i++) {
@ -173,10 +173,9 @@ Status PlainTableReader::PopulateIndex(uint64_t file_size) {
kOffsetLen);
}
size_t count = 0;
for (auto it = tmp_index.begin(); it != tmp_index.end(); ++it) {
if (filter_policy_ != nullptr) {
filter_entries[count++] = it->first;
filter_entries.push_back(it->first);
}
int bucket = GetHashTableBucket(it->first);
@ -194,7 +193,8 @@ Status PlainTableReader::PopulateIndex(uint64_t file_size) {
memcpy(bucket_ptr + key_prefix_len_, &it->second, kOffsetLen);
}
if (filter_policy_ != nullptr) {
filter_policy_->CreateFilter(&filter_entries[0], count, &filter_str_);
filter_policy_->CreateFilter(&filter_entries[0], filter_entries.size(),
&filter_str_);
filter_slice_ = Slice(filter_str_.data(), filter_str_.size());
}

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@ -242,7 +242,9 @@ int main(int argc, char** argv) {
if (FLAGS_plain_table) {
options.allow_mmap_reads = true;
env_options.use_mmap_reads = true;
tf = new rocksdb::PlainTableFactory(16, FLAGS_prefix_len, FLAGS_prefix_len);
tf = new rocksdb::PlainTableFactory(16, FLAGS_prefix_len,
(FLAGS_prefix_len == 16) ? 0 : 8,
0.75);
} else {
tf = new rocksdb::BlockBasedTableFactory();
}