gokvc

gokvc

Fast key-value cache with support of strings, lists, dictionaries and per-key TTL for Go with convenient HTTP API. I tried to keep allocation low to reduce gc pressure. All cache buckets use concurrent stripped maps to reduce lock contention. Reflections and interface{} usage avoided as much as possible to improve performance. Expired keys removed by concurrent gc in batches.

Work in progress edge cases, api changes expected

TODO

• Native client library
• Increase test coverage
• Improve performance
• Scaling
• Persistence

Installation

cd $GOPATH/src/github.com/mmirolim
git clone git@github.com:mmirolim/gokvc.git
cd gokvc
make run

Usage

gokvc -addr=":8081" -log_dir="logs" -stderrthreshold=INFO -v=3

Testing

make test

http api

All params set by using get params. All request has No Cache control headers. Performance wise fasthttp http library used.

Strings

get the value of a key
ADDR /get?k={key} // val

set the string value of a key
ADDR /set?k={key}&v={val}

removes the specified key. A key is ignored if not exist
ADDR /del?k={key}

get the ttl (in seconds) left of a not expired key
ADDR /ttl?k={key}

returns all not expired keys
ADDR /keys // [key1, key2, ...]

returns number of not expired strings
ADDR /slen

Lists

get all values of list by a key
ADDR /lget?k={key} // [val1, val2, ...]

prepend a val to a list. If not exist, list created
ADDR /lpush?k={key}&v={val}&t={ttl} 

remove and get the first element in a list. If empty removes list
ADDR /lpop?k={key} // val

removes the specified list. A key is ignored if not exist
ADDR /ldel?k={key}

get the ttl (in seconds) left of a not expired key
ADDR /lttl?k={key}

returns all not expired keys of lists
ADDR /lkeys // [key1, key2, ...]

returns number of not expired lists
ADDR /lslen

Dictionaries

get all values of list by a key
ADDR /dget?k={key} // map[field1: val1, field2: val2, ...]

prepend a val to a list
ADDR /dfget?k={key}&f={field} // val

set field to dictionary with defined key. If not exist dictionary created
ADDR /dfset?k={key}&f={field}&v={val}&t={ttl}

remove dictionary. A key is ignored if not exist
ADDR /ddel?k={key}

remove entry from dictionary
ADDR /dfdel?k={key}&f={field}

get the ttl (in seconds) left of a not expired key
ADDR /dttl?k={key}

returns all not expired keys of lists
ADDR /dkeys // [key1, key2, ...]

returns number of not expired lists
ADDR /dslen

Benchmarks

Reuslt with Go 1.6 on CPU Core™ i7-5500U @ 2.40GHz × 4 (Fedora23)

Cache API benchmark

go test ./cache -run=none -bench=^Benchmark -cpu=1,3

BenchmarkTimeNow      	50000000	        23.7 ns/op	       0 B/op	       0 allocs/op
BenchmarkTimeNow-3    	50000000	        24.5 ns/op	       0 B/op	       0 allocs/op
BenchmarkSysTime      	500000000	         3.45 ns/op	       0 B/op	       0 allocs/op
BenchmarkSysTime-3    	500000000	         3.64 ns/op	       0 B/op	       0 allocs/op
BenchmarkGetTtl       	20000000	        72.1 ns/op	       0 B/op	       0 allocs/op
BenchmarkGetTtl-3     	20000000	        73.5 ns/op	       0 B/op	       0 allocs/op
BenchmarkSet          	20000000	        80.2 ns/op	       0 B/op	       0 allocs/op
BenchmarkSet-3        	20000000	        82.2 ns/op	       0 B/op	       0 allocs/op
BenchmarkGet          	20000000	        74.7 ns/op	       0 B/op	       0 allocs/op
BenchmarkGet-3        	20000000	        76.7 ns/op	       0 B/op	       0 allocs/op
BenchmarkDel          	20000000	        91.1 ns/op	       0 B/op	       0 allocs/op
BenchmarkDel-3        	20000000	        93.6 ns/op	       0 B/op	       0 allocs/op
BenchmarkParallelSET  	20000000	        84.5 ns/op
BenchmarkParallelSET-3	20000000	        76.0 ns/op
BenchmarkParallelGET  	20000000	        74.8 ns/op
BenchmarkParallelGET-3	20000000	        71.2 ns/op
ok  	github.com/mmirolim/gokvc/cache	26.749s

// github.com/rakyll/boom
boom -n 10000 -c 50 http://localhost:8081/get?k=key1

Summary:
Average:	0.0012 secs
Requests/sec:	41456.5449
Total data:	315648 bytes
Size/request:	31 bytes

Http API benchmarks

go test ./api -run=none -bench=^Benchmark -cpu=1,3

BenchmarkSET  	10000000	       211 ns/op	       0 B/op	       0 allocs/op
BenchmarkSET-3	10000000	       224 ns/op	       0 B/op	       0 allocs/op
BenchmarkGET  	10000000	       124 ns/op	       0 B/op	       0 allocs/op
BenchmarkGET-3	10000000	       129 ns/op	       0 B/op	       0 allocs/op
BenchmarkTTL  	10000000	       124 ns/op	       0 B/op	       0 allocs/op
BenchmarkTTL-3	10000000	       129 ns/op	       0 B/op	       0 allocs/op
ok  	github.com/mmirolim/gokvc/api	10.436s