README
¶
bitcask
This is my toy project to learn golang.
Bitcask is a key-value log database. It produce value in file and store key to value's location to find it. location is consist of
- fileno
- offset
- length
Every time add a key value would append log to a value file and a header file with locations.
And when reading, just find the location and read it from disk. A cache for recent key makes reading faster.
In option.go, there are some options for DB. such as go's cnt for reader, max file size, max key and value length.
I also add location header & checksum to avoid disk fail when loading.
I learn a lot in this project.
- R/W files and handle errors
- channel works like a thread safe queue.
- again importance of tests
There still some works to do. Such as
- Managing readers to reduce system call of opening same file.
- A monitor for deleting not outdated logs in files when idle.
- Appending logs in multiple files, which makes more writers possible.(currently only one)
- Recover for db's failure. A bug now is that it won't check sucess in creating new value files but not in header files. When this happen, loading return error.
But I want to do some more influential work and have no interest in this toy project anymore.
Documentation
¶
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ErrCxtInconsistency = errors.New("cxt: inconsistency")
var ErrCxtInvalid = errors.New("cxt: other files")
var ErrDuplicateOption = errors.New("duplicate option")
var ErrKeyLenTooLong = errors.New("key too long")
var ErrKeyNotFound = errors.New("not found key")
var ErrNotReady = errors.New("not ready")
var ErrRead = errors.New("read")
var ErrValueLenTooLong = errors.New("value too long")
var ErrWrite = errors.New("write")
Functions ¶
This section is empty.
Types ¶
type CacheOption ¶
type CacheOption struct {
Capacity int
}
Source Files
Directories