Go-mdbm

• Go-mdbm is a Go(golang,go-lang) binds to Yahoo! MDBM C API.
• MDBM is a super-fast memory-mapped key/value store.
• MDBM is an ndbm work-alike hashed database library based on sdbm which is based on Per-Aake Larson’s Dynamic Hashing algorithms.
• MDBM is a high-performance, memory-mapped hash database similar to the homegrown libhash.
• The records stored in a mdbm database may have keys and values of arbitrary and variable lengths.

Table of Contents

• Install from Source Code
  • Y! MDBM
  • Downloading
  • Compiling
• Install from Pre-build Packages
  • Ubuntu
  • go-mdbm
  • Install
• Download for Development or Customization
  • Build
  • Testing
  • Run to Example
  • Miscellaneous
  • Support two compatibility branches
• Not Support APIs
  • Deprecated APIs
  • Only a V2 implementation
  • Alternative
  • As soon
• Examples
• Benchmark
  • Spec
  • Command
  • Output
• Additional Benchmarks
  • Spec
    • Command
    • Output
    • DB File
  • Command
    • Output
    • DB File
  • Command
    • Output
    • DB File
  • Spec
  • Command
    • Output
    • DB File
  • Command
    • Output
    • DB File
  • Command
    • Output
    • DB File
• Links

Install from Source Code

Y! MDBM

Downloading

Use the master branch

git clone https://github.com/yahoo/mdbm.git

OR Use the release tarball, Guess you will using it

wget https://github.com/yahoo/mdbm/archive/v4.12.3.tar.gz
tar xvzf v4.12.3.tar.gz

Compiling

Refer to the https://github.com/yahoo/mdbm/blob/master/README.build if you want to install to another path, (HIGH RECOMMEND)

cd mdbm
PREFIX=/usr/local/mdbm make install

Install from Pre-build Packages

• Ubuntu Package
• RedHat(CentOS) Package
• OSX Package (as soon)
• BSD Port (as soon)

Ubuntu

dpkg -i pkg/ubunt/mdbm-XXXX_XXXX.dep
echo "/usr/local/mdbm/lib64/" >> /etc/ld.so.conf

go-mdbm

Install

CGO_CFLAGS="-I/usr/local/mdbm/include/ -I./" \
CGO_LDFLAGS="-L/usr/local/mdbm/lib64/ -Wl,-rpath=/usr/local/mdbm/lib64/ -lmdbm" \
go get github.com/torden/go-mdbm

Download for Development or Customization

git clone https://github.com/torden/go-mdbm

Build

cd $GOPATH/src/github.com/torden/go-mdbm

make clean
make setup
make build

Testing

cd $GOPATH/src/github.com/torden/go-mdbm
make test

Run to Example

cd $GOPATH/src/github.com/torden/go-mdbm/example/
go run -race example.go

Miscellaneous

The following is support to development

make help

build:             Build the go-mdbm
clean::            Clean-up
cover:             Generate a report about coverage
coveralls::        Send a report of coverage profile to coveralls.io
help::             Show Help
installpkgs::      Install Packages
lint:              Run a LintChecker (Normal)
metalinter::       Install GoMetaLinter
pprof:             Profiling
report:            Generate the report for profiling
setup:             Setup Build Environment
strictlint:        Run a LintChecker (Strict)
test:              Run Go Test with Data Race Detection

Support two compatibility branches

Branch	Support	test
master	yes	always
release 4.3.x	yes	tested

Not Support APIs

Unfortunately, the following list is not supported on now. If you want them, please feel free to raise an issue

Deprecated APIs

API	STATUS	COMMENT
mdbm_save	DEPRECATED	mdbm_save is only supported for V2 MDBMs.
mdbm_restore	DEPRECATED	mdbm_restore is only supported for V2 MDBMs.
mdbm_sethash	DEPRECATED	Legacy version of mdbm_set_hash() This function has inconsistent naming, an error return value. It will be removed in a future version.

Only a V2 implementation

API	STATUS	COMMENT
mdbm_stat_all_page	V3 not supported	There is only a V2 implementation. V3 not currently supported.
mdbm_stat_header	V3 not supported	There is only a V2 implementation. V3 not currently supported.

Alternative

API	COMMENT
mdbm_fetch_buf	Fetch, FetchStr APIs

As soon

API	STATUS
mdbm_set_backingstore	as soon
mdbm_cdbdump_add_record	as soon
mdbm_cdbdump_import	as soon
mdbm_dbdump_to_file	as soon
mdbm_dbdump_trailer_and_close	as soon
mdbm_dbdump_export_header	as soon
mdbm_iterate	as soon
mdbm_prune	as soon
mdbm_set_stats_func	as soon
mdbm_chunk_iterate	as soon

Examples

See the Documentations for more details

Benchmark

The following is result of Go-mdbm vs BoltDB benchmarks for simple data storing and random fetching in them.

• Source Code
• MDBM::Performance

Spec

Type	Spec
Machine	VM(VirtualBox)
OS	Ubuntu 17.10 (Artful Aardvark)
CPU	2 vCore
RAM	8G
BoltDB Ver.	9da3174 on 20 Nov
Mdbm Ver.	893f7a8 on 26 Jul

Command

CGO_CFLAGS="-I/usr/local/mdbm/include/ -I./" CGO_LDFLAGS="-L/usr/local/mdbm/lib64/ -Wl,-rpath=/usr/local/mdbm/lib64/ -lmdbm" \
go test -race -bench=. -run Benchmark -test.benchmem -v

Output

func	count of loop	nano-seconds per loop	bytes per operation	allocations per operation
Benchmark_boltdb_Store-2	2000	1082487 ns/op	38110 B/op	59 allocs/op
Benchmark_mdbm_Store-2	500000	2845 ns/op	96 B/op	6 allocs/op
Benchmark_mdbm_StoreWithLock-2	500000	2908 ns/op	96 B/op	6 allocs/op
Benchmark_boltdb_Fetch-2	200000	9199 ns/op	496 B/op	9 allocs/op
Benchmark_mdbm_Fetch-2	1000000	1824 ns/op	56 B/op	4 allocs/op
Benchmark_mdbm_FetchWithLock-2	1000000	2025 ns/op	56 B/op	4 allocs/op
Benchmark_mdbm_PreLoad_Fetch-2	1000000	1811 ns/op	56 B/op	4 allocs/op
Benchmark_mdbm_PreLoad_FetchWithLock-2	500000	2038 ns/op	56 B/op	4 allocs/op

Additional Benchmarks

Spec

Type	Spec
Machine	VM(VirtualBox)
OS	Ubuntu 17.10 (Artful Aardvark)
CPU	2 vCore
RAM	8G
BoltDB Ver.	9da3174 on 20 Nov
Mdbm Ver.	893f7a8 on 26 Jul

Command

CGO_CFLAGS="-I/usr/local/mdbm/include/ -I./" CGO_LDFLAGS="-L/usr/local/mdbm/lib64/ -Wl,-rpath=/usr/local/mdbm/lib64/ -lmdbm"
go test -race -bench=. -run Benchmark -test.benchmem -v \

Output

Benchmark_boltdb_Store-2                            2000           1072628 ns/op           37994 B/op         59 allocs/op
Benchmark_boltdb_Fetch-2                          200000              8960 ns/op             496 B/op          9 allocs/op
Benchmark_mdbm_Store-2                            500000              2923 ns/op              96 B/op          6 allocs/op
Benchmark_mdbm_StoreWithLock-2                    500000              3055 ns/op              96 B/op          6 allocs/op
Benchmark_mdbm_Fetch-2                           1000000              1823 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_FetchWithLock-2                   1000000              2093 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_Fetch-2                   1000000              1825 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_FetchWithLock-2            500000              2084 ns/op              56 B/op          4 allocs/op

DB File

Type	File Size	Times	elapsed time
BoltDB	128K	10000	1168516ns
MDBM(Store)	32M	3000000	2937ns

Command

CGO_CFLAGS="-I/usr/local/mdbm/include/ -I./" CGO_LDFLAGS="-L/usr/local/mdbm/lib64/ -Wl,-rpath=/usr/local/mdbm/lib64/ -lmdbm" \
go test -race -bench=. -run Benchmark -test.benchmem -v -test.benchtime 3s

Output

Benchmark_boltdb_Store-2                            5000           1168516 ns/op           39249 B/op         59 allocs/op
Benchmark_boltdb_Fetch-2                          500000              9146 ns/op             496 B/op          9 allocs/op
Benchmark_mdbm_Store-2                           2000000              2937 ns/op              96 B/op          6 allocs/op
Benchmark_mdbm_StoreWithLock-2                   1000000              3015 ns/op              96 B/op          6 allocs/op
Benchmark_mdbm_Fetch-2                           2000000              1891 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_FetchWithLock-2                   2000000              2185 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_Fetch-2                   2000000              1975 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_FetchWithLock-2           2000000              2129 ns/op              56 B/op          4 allocs/op

DB File

Type	File Size	Times	elapsed time
BoltDB	256K	10000	1168516ns
MDBM(Store)	128M	3000000	2937ns

Command

CGO_CFLAGS="-I/usr/local/mdbm/include/ -I./" CGO_LDFLAGS="-L/usr/local/mdbm/lib64/ -Wl,-rpath=/usr/local/mdbm/lib64/ -lmdbm" \
go test -race -bench=. -run Benchmark -test.benchmem -v -test.benchtime 10s

Output

Benchmark_boltdb_Store-2                           10000           1115691 ns/op           41109 B/op         60 allocs/op
Benchmark_mdbm_Store-2                           5000000              2933 ns/op              96 B/op          6 allocs/op
Benchmark_mdbm_StoreWithLock-2                   5000000              3098 ns/op              96 B/op          6 allocs/op
Benchmark_boltdb_Fetch-2                         2000000              9200 ns/op             496 B/op          9 allocs/op
Benchmark_mdbm_Fetch-2                          10000000              1802 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_FetchWithLock-2                  10000000              2049 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_Fetch-2                  10000000              1802 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_FetchWithLock-2          10000000              2038 ns/op              56 B/op          4 allocs/op

DB File

Type	File Size	Times	elapsed time
BoltDB	512K	10000	1115691ns
MDBM(Store)	257M	5000000	2933ns

Spec

Type	Spec
Machine	Physical
OS	Ubuntu 17.10 (Artful Aardvark)
CPU	8 Core (Intel i7)
RAM	16G
HDD	SSD
BoltDB Ver.	9da3174 on 20 Nov
Mdbm Ver.	893f7a8 on 26 Jul

Command

#CPU : 8core
#RAM : 16g
CGO_CFLAGS="-I/usr/local/mdbm/include/ -I./" CGO_LDFLAGS="-L/usr/local/mdbm/lib64/ -Wl,-rpath=/usr/local/mdbm/lib64/ -lmdbm" \
go test -race -bench=. -run Benchmark -test.benchmem -v

Output

Benchmark_boltdb_Store-8                             300           6138312 ns/op           32704 B/op         55 allocs/op
Benchmark_mdbm_Store-8                            200000              5235 ns/op              96 B/op          6 allocs/op
Benchmark_mdbm_StoreWithLock-8                    200000              5749 ns/op              96 B/op          6 allocs/op
Benchmark_boltdb_Fetch-8                          100000             15322 ns/op             496 B/op          9 allocs/op
Benchmark_mdbm_Fetch-8                            500000              2852 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_FetchWithLock-8                    300000              3713 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_Fetch-8                    500000              2829 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_FetchWithLock-8            500000              3436 ns/op              56 B/op          4 allocs/op

DB File

Type	File Size	Times	elapsed time
BoltDB	64K	300	6138312ns
MDBM(Store)	16M	200000	5235ns

Command

CGO_CFLAGS="-I/usr/local/mdbm/include/ -I./" CGO_LDFLAGS="-L/usr/local/mdbm/lib64/ -Wl,-rpath=/usr/local/mdbm/lib64/ -lmdbm" \
go test -race -bench=. -run Benchmark -test.benchmem -v -test.benchtime 3s

Output

Benchmark_boltdb_Store-8                            1000           6283664 ns/op           37533 B/op         58 allocs/op
Benchmark_mdbm_Store-8                           1000000              4780 ns/op              96 B/op          6 allocs/op
Benchmark_mdbm_StoreWithLock-8                   1000000              5360 ns/op              96 B/op          6 allocs/op
Benchmark_boltdb_Fetch-8                          300000             14556 ns/op             496 B/op          9 allocs/op
Benchmark_mdbm_Fetch-8                           2000000              2772 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_FetchWithLock-8                   1000000              3104 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_Fetch-8                   2000000              2527 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_FetchWithLock-8           1000000              3256 ns/op              56 B/op          4 allocs/op

DB File

Type	File Size	Times	elapsed time
BoltDB	128K	1000	6283664ns
MDBM(Store)	64M	1000000	4780ns

Command

CGO_CFLAGS="-I/usr/local/mdbm/include/ -I./" CGO_LDFLAGS="-L/usr/local/mdbm/lib64/ -Wl,-rpath=/usr/local/mdbm/lib64/ -lmdbm" \
go test -race -bench=. -run Benchmark -test.benchmem -v -test.benchtime 10s

Output

Benchmark_boltdb_Store-8                            2000           6133872 ns/op           28366 B/op         59 allocs/op
Benchmark_mdbm_Store-8                           3000000              5377 ns/op              96 B/op          6 allocs/op
Benchmark_mdbm_StoreWithLock-8                   3000000              5145 ns/op              96 B/op          6 allocs/op
Benchmark_boltdb_Fetch-8                         1000000             15703 ns/op             496 B/op          9 allocs/op
Benchmark_mdbm_Fetch-8                           5000000              2631 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_FetchWithLock-8                   5000000              3245 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_Fetch-8                   5000000              2598 ns/op              56 B/op          4 allocs/op
Benchmark_mdbm_PreLoad_FetchWithLock-8           5000000              3379 ns/op              56 B/op          4 allocs/op

DB File

Type	File Size	Times	elapsed time
BoltDB	128K	2000	6133872ns
MDBM(Store)	256M	3000000	5377ns

Links

• Yahoo! MDBM
• MDBM::Concept
• MDBM::Build
• MDBM::Document
• MDBM::FAQ
• DBM
• BoltDB
• PHP-MDBM
• Py-MDBM

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Please feel free. I hope it is helpful for you