Ardb is a BSD licensed, redis-protocol compatible persistent storage server, it support different storage engines. Currently LevelDB/LMDB/RocksDB are supported, but only LevelDB engine is well tested.
LevelDB is the default storage engine, to compile with leveldb, just type 'make' to compile server & lib & tests.
To use LMDB/RocksDB as storage engine, you should set env 'storage_engine' first.
storage_engine=lmdb make
storage_engine=rocksdb make
It should compile to several executables in 'src' directory, such as ardb-server, ardb-test etc.
- Full redis-protocol compatibility
- 2d spatial index supported. Spatial Index
- Most redis commands supported, and a few new commands
- Different storage engine supported (LevelDB/KyotoCabinet/LMDB/RocksDB)
- Replication compatible with Redis 2.6/2.8
- Ardb instance work as slave of Redis 2.6/2.8+ instance
- Ardb instance work as master of Redis 2.6/2.8+ instance
- Ardb instance work as slave of Ardb instance
- Replication detail
- Auto failover support by redis-sentinel
- Backup data online
- Use 'save/bgsave' to backup data
- Use 'import' to import backup data
- Backup & Restore
Since ardb is a full redis-protocol compatible server, you can use any redis client to connect it. Here lists all redis clients. http://www.redis.io/clients
Benchmarks were all performed on a four-core Intel(R) Xeon(R) CPU E5520@2.27GHz, with 64 GB of DDR3 RAM, 500 GB of SCSI disk
The benchmark tool is 'redis-benchmark' from redis,50 parallel clients, 10000000 requests, 1000000 random keys each test case. There would be no benchmark test for RocksDB engine because of OS and compiler version limit in the test machine.
GCC Version:4.8.3
OS Version: Red Hat Enterprise Linux AS release 4 (Nahant Update 3)
Kernel Version: 2.6.32_1-10-6-0
Redis Version: 2.8.9
Ardb Version: 0.7.2(LMDB 0.9.11, LevelDB1.16.0, RocksDB3.1)
LevelDB Options: thread_pool_size=2, block_cache_size=512m, write_buffer_size=128m, compression=snappy
RocksDB Options: thread_pool_size=2, block_cache_size=512m, write_buffer_size=128m, compression=snappy
LMDB Option: thread_pool_size=2, database_max_size=10G, readahead=no
Becnhmark data(./redis-benchmark -r 10000000 -n 10000000):
LevelDB LMDB RocksDB Redis
PING_INLINE 95075.11 91945.56 92274.76 79669.85
PING_BULK 99265.43 92988.66 95721.27 90044.66
SET 62361.64 72490.03 55567.91 73692.51
GET 69045.99 93805.12 68078.16 82459.95
INCR 47572.16 59805.03 34883.32 74940.61
LPUSH 47369.57 27713.11 40584.42 105466.32
LPOP 14205.29 14711.51 10088.27 105797.72
SADD 37583.39 41779.82 24421.81 100405.64
SPOP 109.326 17614.32 87.634 75253.04
LPUSH(for LRANGE) 49504.95 16998.71 40719.93 87989.45
LRANGE_100 7981.99 17639.79 7445.68 45831.61
LRANGE_300 3829.91 6578.86 3113.99 17608.11
LRANGE_500 2504.61 4552.06 2156.08 12345.07
LRANGE_600 1734.72 3082.94 1650.46 7906.01
MSET (10 keys) 9675.48 7204.56 5255.44 35967.6
- Note:
- Ardb uses 2 threads in benchmark test, while redis is single threaded application. That's the reason ardb is faster than redis in some test cases.
- LevelDB & LMDB both use tree like structure on disk, more data is stored, the server is slower.
- 'SPOP' is very slow with LevelDB engine
- Unsupported Redis Commands:
- DUMP
- MIGRATE
- OBJECT
- RESTORE
- CONFIG RESETSTAT
- DEBUG
- MONITOR
- BITPOS
- PUBSUB
- Additional Commands:
- HClear/SClear/ZClear/LClear
- SUnionCount/SInterCount/SDiffCount
- ZAdd with limit
- ZPop/ZRPop
- HMIncrby
- __SET__/__DEL__(for replication)
- CompactDB/CompactAll
- BitOPCount
- Import
- KeysCount
- GeoAdd
- GeoSearch
- Cache
###Memory Usage In basho's fork of leveldb project, they give a way to estimate memory usage of a database.
write_buffer_size*2
+ max_open_files*4194304
+ (size in NewLRUCache initialization)
If you want to limit the total memory usage, you should tweak configuration options whoose names start with 'leveldb.' in ardb.conf.