pmemkv-bench

Benchmark for pmemkv and its underlying libraries, based on leveldb's db_bench.

This is experimental pre-release software and should not be used in production systems. APIs and file formats may change at any time without preserving backwards compatibility. All known issues and limitations are logged as GitHub issues.

Benchmarking

The pmemkv_bench utility provides some standard read & write benchmarks. This is based on the db_bench utility included with LevelDB and RocksDB, although the list of supported parameters is slightly different.

The pmemkv-bench may clear or remove pool passed in --db parameter, so pool, poolset or DAX device which contain existing data shouldn't be used.

To build pmemkv_bench:

make bench

Supported runtime parameters:

--engine=<name>            (storage engine name, default: cmap)
--db=<location>            (path to persistent pool, default: /dev/shm/pmemkv)
                           (note: file on DAX filesystem, DAX device, or poolset file)
--db_size_in_gb=<integer>  (size of persistent pool to create in GB, default: 0)
                           (note: always use 0 with poolset or device DAX configs)
--histogram=<0|1>          (show histograms when reporting latencies)
--num=<integer>            (number of keys to place in database, default: 1000000)
--reads=<integer>          (number of read operations, default: 1000000)
--threads=<integer>        (number of concurrent threads, default: 1)
--value_size=<integer>     (size of values in bytes, default: 100)
--benchmarks=<name>,       (comma-separated list of benchmarks to run)
    fillseq                (load N values in sequential key order)
    fillrandom             (load N values in random key order)
    overwrite              (replace N values in random key order)
    readseq                (read N values in sequential key order)
    readrandom             (read N values in random key order)
    readmissing            (read N missing values in random key order)
    deleteseq              (delete N values in sequential key order)
    deleterandom           (delete N values in random key order)
    readwhilewriting       (1 writer, N threads doing random reads)
    readrandomwriterandom  (N threads doing random-read, random-write)

Benchmarking on emulated persistent memory:

PMEM_IS_PMEM_FORCE=1 ./pmemkv_bench --db=/dev/shm/pmemkv --db_size_in_gb=1

Benchmarking on filesystem DAX:

./pmemkv_bench --db=/mnt/pmem/pmemkv --db_size_in_gb=1

Benchmarking on device DAX:

./pmemkv_bench --db=/dev/dax1.0

Benchmarking with poolset:

./pmemkv_bench --db=~/pmemkv.poolset

Setting up environment

If pmemkv is installed in some non-standard path, LD_LIBRARY_PATH variable should be set to the directory which contains libpmemkv.so.1 file

export LD_LIBRARY_PATH=</path/to/libpmemkv>