pmemkv-tools

Optional tools and utilities for pmemkv

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.

To build pmemkv_bench:

make bench

Supported runtime parameters:

--engine=<name>            (storage engine name, default: kvtree3)
--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)

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:

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

Benchmarking on device DAX:

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

Benchmarking with poolset:

PMEM_IS_PMEM_FORCE=1 ./pmemkv_bench --db=~/pmemkv.poolset

Baselines

Baseline tests are simple single-threaded tests that compare average per-operation latency between different language bindings and the blackhole engine. These are used to analyze and improve performance of our language bindings.

make baseline_c
make baseline_cpp
make baseline_java
make baseline_nodejs
make baseline_ruby

Examples

These are small example programs used in our documentation.

make example_c
make example_cpp
make example_java
make example_nodejs
make example_ruby