ICPP22hdpsr
You should prepare a machine running Ubuntu16.04 and configure the Golang environment in advance.
To download the project:
git clone https://github.com/YuchongHu/hdpsr.git
Then download the module:
go mod tidy
-
erasure-global.gocontains the system-level interfaces and global structs and variables -
erasure-init.gocontains the basic config file(.hdr.sys) read and write operation, once there is file change, we update the config file. -
erasure-errors.gocontains the definitions for various possible errors. -
erasure-encode.gocontains operation for striped file encoding, one great thing is that you could specify the data layout. -
erasure-layout.goYou could specific the layout, for example, random data distribution or some other heuristics. -
erasure-read.gocontains operation for striped file reading, if some parts are lost, we try to recover. -
erasure-update.gocontains operation for striped file updating, if some parts are lost, we try to recover. -
erasure-recover.godeals with multi-disk recovery, concerning both data and meta data. -
erasure-update.gocontains operation for striped file updating, if some parts are lost, we try to recover first. -
fsr.gocontains operation for full-stripe-repair -
psrap.gocontains operation for active preliminary partial-stripe-repair (single-disk repair) -
psras.gocontains operation for active slower-first partial-stripe-repair (single-disk repair) -
psrpa.gocontains operation for passive partial-stripe-repair (single-disk repair) -
m-psrap.gocontains operation for active preliminary partial-stripe-repair (multi-disk repair) -
m-psras.gocontains operation for active slower-first partial-stripe-repair (multi-disk repair) -
m-psrpa.gocontains operation for passive partial-stripe-repair (multi-disk repair)
import: reedsolomon library
A complete demonstration of various CLI usage lies in examples/build.sh. You may have a glimpse.
Here we elaborate the steps as following, in dir ./examples:
- Build the project:
go build -o main ./main.go
- New a file named
.hdr.disks.pathin./examples, list the path of your local disks, e.g.,
/home/server1/data/data1
/home/server1/data/data2
/home/server1/data/data3
/home/server1/data/data4
/home/server1/data/data5
/home/server1/data/data6
/home/server1/data/data7
/home/server1/data/data8
/home/server1/data/data9
/home/server1/data/data10
/home/server1/data/data11
/home/server1/data/data12
/home/server1/data/data13
/home/server1/data/data14
/home/server1/data/data15
/home/server1/data/data16
Please remind that carriage return (CR), line feed (LF) are not allowed in the last line.
- Initialise the system, you should explictly attach the number of data(k) and parity shards (m) as well as blocksize (in bytes), remember k+m must NOT be bigger than 256.
./main -md init -k 12 -m 4 -bs 4096 -dn 16
bs is the blockSize in bytes and dn is the diskNum you intend to use in .hdr.disks.path. Obviously, you should spare some disks for fault torlerance purpose.
- Encode one examplar file.
./main -md encode -f {input file path} -o
- decode(read) the examplar file.
./grasure -md read -f {input file path} -conStripes 100 -sp {output file path}
- check the hash string to see encode/decode is correct.
sha256sum {input file path}
sha256sum {output file path}
- To delete the file in storage (currently irreversible, we are working on that):
./main -md delete -f {filebasename} -o
- To update a file in the storage:
./main -md update -f {filebasename} -nf {local newfile path} -o
- To recover a file via full-stripe-repair
./main -md fsr -fmd diskFail -fn 1 -f {input file path}
use `fn` to simulate the failed number of disks (default is 0), for example, `-fn 2` simluates shutdown of arbitrary two disks
- To recover a file via partial-stripe-repair
./main -md psrap -fmd diskFail -fn 1 -f {input file path}
./main -md psras -fmd diskFail -fn 1 -f {input file path}
./main -md psrpa -fmd diskFail -fn 1 -f {input file path}
- To recover a file with multi-disk failures via partial-stripe-repair
./main -md mpsrap -fmd diskFail -fn 1 -f {input file path}
./main -md mpsras -fmd diskFail -fn 1 -f {input file path}
./main -md mpsrpa -fmd diskFail -fn 1 -f {input file path}
the command-line parameters of ./examples/main.go are listed as below.
| parameter(alias) | description | default |
|---|---|---|
| blockSize(bs) | the block size in bytes | 4096 |
| mode(md) | the mode of ec system, one of (encode, decode, update, scaling, recover) | |
| dataNum(k) | the number of data shards | 12 |
| parityNum(m) | the number of parity shards(fault tolerance) | 4 |
| diskNum(dn) | the number of disks (may be less than those listed in .hdr.disk.path) |
4 |
| filePath(f) | upload: the local file path, download&update: the remote file basename | |
| savePath | the local save path (local path) | file.save |
| newDataNum(new_k) | the new number of data shards | 32 |
| newParityNum(new_m) | the new number of parity shards | 8 |
| recoveredDiskPath(rDP) | the data path for recovered disk, default to /tmp/restore | /tmp/restore |
| override(o) | whether to override former files or directories, default to false | false |
| conWrites(cw) | whether to enable concurrent write, default is false | false |
| conReads(cr) | whether to enable concurrent read, default is false | false |
| failMode(fmd) | simulate [diskFail] or [bitRot] mode" | diskFail |
| failNum(fn) | simulate multiple disk failure, provides the fail number of disks | 0 |
| conStripes(cs) | how many stripes are allowed to encode/decode concurrently | 100 |
| quiet(q) | whether or not to mute outputs in terminal | false |
| log(l) | whether or not to write the repair time to a file called log.txt |
false |