Yet another write-optimized storage engine, using buffered B-tree algorithm inspired by TokuDB.
- Provides a key-value access API similar to LevelDB.
- Support Snappy compression.
- Support Direct IO and Linux AIO.
CascaDB can have better performance if google snappy library 're installed. Otherwise data blocks're not compressed.
CascaDB utilizes CMake to build, so first of all you should install CMake.
It's recommended to make out of source build, that is, object files are generated into a separated directory with the source directory.
mkdir build
cd build
cmake ..
make && make install
Running bin/db_bench to get detailed performance report of how CascaDB running on your machine.
e.g. bin/db_bench --num=1000000
, This will create and test on a database of a million records, each record has a 16 byte key, and a 100 byte value.
fillseq : 1.020 micros/op;
fillrandom : 2.559 micros/op;
Read benchmark results after sequential insertions
readrandom : 1.125 micros/op;
readseq : 1.282 micros/op;
Read benchmark results after random insertions
readrandom : 3.227 micros/op;
readseq : 1.295 micros/op;
- Include the header file.
#include <cascadb/db.h>
- Open the database.
Options opts;
opts.dir = create_fs_directory("/tmp/db_bench");
opts.comparator = new LexicalComparator();
opts.compress = kSnappyCompress;
const char *dbname = "example";
DB *db = DB::open(dbname, opts);
if (!db) {
fprintf(stderr, "open error %s\n", dbname);
exit(1);
}
- Insert record.
if (!db->put("This is the key", "This is the value")) {
fprintf(stderr, "put error\n");
}
- Read record.
Slice value;
if (!db->get("This is the key", value)) {
fprintf(stderr, "get error\n");
}
fprintf(stdout, "the value is %s\n", value.to_string().c_str());
- Delete record.
if (!db->del("This is the key")) {
fprintf(stderr, "del error\n");
}
- Destory database.
delete db;
delete opts.comparator;
delete opts.dir;
- Add forward and backward iteration over data.
- Support more compression methods.
- Implement write ahead log to ensure write operation is atomic.