Ghost

Yet another in-memory key/value storage written in Go.

Description

Simple key/value storage. Based on Striped hashmap algorithm.

Features

• Concurrency safe
• Fast
• Written in pure Go, means could be used in any place where Go could be run
• Could be used as embedded storage
• Could be run as standalone server

Commands

Server commands:

• PING -- Test command. Returns "Pong!".

Hash commands:

• SET <key> <value> -- Set create or update <key> with <value>.
• GET <key> -- Get value of the <key>.
• DEL <key> -- Delete key <key>.

Collection commands:

• CGET <collection name> -- Change user's collection.
• CADD <collection name> -- Create new collection.

Server

####Build server:

make ghost-server

####Run server:

ghost -host localhost -port 6869

Benchmark

####Build:

make ghost-benchmark

Usage of ghost-benchmark:
  -clients int
        Number of paralel connections (default 50)
  -embedded
        Test embedded storage
  -host string
        Server hostname (default "localhost")
  -keyrange int
        Use random keys for SET/GET (default 100)
  -pooltimeout int
        Client PoolTimeout option (default 10)
  -port int
        Server port (default 6869)
  -requests int
        Total number of requests (default 10000)
  -size int
        Data size of SET/GET value in bytes (default 2)
  -socket string
        Listen to unix socket

Client

package main

import (
	"fmt"

	"github.com/alexyer/ghost/client"
)

func main() {
    // Create new client and connect to the Ghost server.
	ghost := client.New(&client.Options{
		Addr: "localhost:6869",
	})

	ghost.Set("key1", "val2")      // Set key
	res, err := ghost.Get("key1")  // Get key
	ghost.Del("key1")              // Del key

	ghost.CAdd("new-collection")  // Create new collection
	ghost.CGet("new-collection")  // Change client collection
}

CLI

Now you can use a simple cli to test or play with data. All the current commands are supported. Cli works only if ghost-server exists on provided address.

####Build:

make ghost-cli

####Run cli:

ghost-cli -host localhost -port 6869

Example session:

> ping # will test the connection
Pong!
> set hello world # will set value "world" to key "hello"
OK
> get hello # will get the value stored with key "hello"
world
> del hello # will delete the value stored with key "hello"
OK
> cadd mars # will add new "mars" collection
OK
> cget mars # will select "mars" collection
OK
> set "few words key" "few words value" # if few words in value or keys is needed surround it with quotes
OK
> get "few words key"
few words value
> set song "riders on the storm" # only one argument could be in quotes if needed
OK
> get song
riders on the storm
> set "another song" stairway # other order is possible
OK
> get "another song"
stairway
# cli also supports two utility command:
> help # to get the help message
> quit # to correct way out of cli

Embedded

Benchmark

Ghost hashmap

BenchmarkSet-4            	  500000	      4625 ns/op
BenchmarkGet-4            	10000000	       101 ns/op
BenchmarkDel-4            	20000000	        75.1 ns/op

Ghost concurrent hashmap

BenchmarkParallelSet-4    	  300000	      3680 ns/op
BenchmarkParallelSet8-4   	  500000	      4050 ns/op
BenchmarkParallelSet64-4  	  500000	      4107 ns/op
BenchmarkParallelSet128-4 	  500000	      4132 ns/op
BenchmarkParallelSet1024-4	  300000	      4256 ns/op

BenchmarkParallelGet-4    	20000000	       116 ns/op
BenchmarkParallelGet8-4   	20000000	       133 ns/op
BenchmarkParallelGet64-4  	20000000	       136 ns/op
BenchmarkParallelGet128-4 	20000000	       142 ns/op
BenchmarkParallelGet1024-4	20000000	       137 ns/op

BenchmarkParallelDel-4    	10000000	       122 ns/op
BenchmarkParallelDel8-4   	10000000	       152 ns/op
BenchmarkParallelDel64-4  	10000000	       154 ns/op
BenchmarkParallelDel128-4 	10000000	       154 ns/op
BenchmarkParallelDel1024-4	10000000	       156 ns/op

Native hashmap

BenchmarkNativeSet-4      	 3000000	       338 ns/op
BenchmarkNativeGet-4      	30000000	        41.3 ns/op
BenchmarkNativeDel-4      	100000000	        15.5 ns/op

Example

package main

import (
        "fmt"

        "github.com/alexyer/ghost"
)

func main() {
        //Storage
        storage := ghost.GetStorage() // Get storage instance

        storage.AddCollection("newcollection")          // Create new collection
        mainCollection := storage.GetCollection("main") // Get existing collection
        storage.DelCollection("newcollection")          // Delete collection

        // Collections
        mainCollection.Set("somekey", "42") // Set item

        val, _ := mainCollection.Get("somekey") // Get item from Collection
        fmt.Println(val)

        mainCollection.Del("somekey") // Delete item
}

TODO

Release Milestone

Contributing

It's learing project, so there are possible a lot of issues, espesially in concurrent code, so any improvements, critics or propsals are highly appretiated.