Artifact Review Summary: Geometric Partitioning: Explore the Boundary of Optimal Erasure Code Repair

Artifact Details

Badges Awarded

Artifact Available	Artifact Functional

Description of the Artifact

RCStor is open-sourced at https://github.com/rcstor/rcstor

The artifact, written in Golang, is a distributed object store prototype with REST API support. This prototype uses the erasure code repair design described in the paper.

Environment(s) Used for Testing

All reviewers are using CloudLab, Ubuntu 18, with 16 machines of c6525-100g, 16 machines of c6525-25g, or 16 machines of c6320. The detailed machine setup can be found in https://docs.cloudlab.us/hardware.html

Step-By-Step Instructions to Exercise the Artifact

Setup the 16 instances in CloudLabs. They have IP addresses 10.10.1.1 to 10.10.1.16.
Run the following commands on each machine and then restart the instance.

sudo su
wget https://dl.google.com/go/go1.14.10.linux-amd64.tar.gz
tar -xvf go1.14.10.linux-amd64.tar.gz -C /usr/local/
echo 'export GOROOT=/usr/local/go' >> ~/.profile
echo 'export GOPATH=$HOME/go' >> ~/.profile
echo 'export PATH=$GOPATH/bin:$GOROOT/bin:/usr/local/bin:$PATH' >> ~/.profile
source ~/.profile
apt update
apt install openssh-client openssh-server -y
systemctl start sshd
ssh-keygen
echo 'root   soft    nofile      1048576' >> /etc/security/limits.conf
echo 'root   hard    nofile      1048576' >> /etc/security/limits.conf

(It is necessary to increase the limit of the number of opened files, because the artifact opens many connections.)

Run sudo su on all the instances after restarting.
On the first server, run:

git clone https://github.com/rcstor/rcstor.git
cd rcstor
make install

Run the following commands on each machine to copy the SSH keys:

ssh-copy-id root@10.10.1.1 -o StrictHostKeyChecking=no
...
ssh-copy-id root@10.10.1.16 -o StrictHostKeyChecking=no

Mount the storage on each machine:

apt install xfsprogs -y
mkfs -t xfs /dev/sda4
mkdir /mnt/geop
mount /dev/sda4 /mnt/geop

Create the following JSON file following the instructions.

{
  "VolumeName": "Geometric-1M",
  "Servers" : [
    {
      "IP" : "10.10.1.1",
      "Dir" : [
        "/mnt/geop"
      ]
    },
    ...
    {
      "IP" : "10.10.1.16",
      "Dir" : [
        "/mnt/geop"
      ]
    }
  ],
  "VolumeParameter" : {
    "nPG" : 200,
    "Layout" : "Geometric",
    "K" : 10,
    "Redundancy" : 4,
    "MinBlockSize" : 1048576,
    "MaxBlockSize" : 268435456,
    "GeometricBase" : 2,
    "IsSSD" : false,
    "HTTPPort" : 8080
  }
}

Start the service using this new JSON file.
Use the README.md to test the PUT/GET method of the storage server.
Use the genParity method to generate the parity, and then test the DGET method.
Test the recovery.
Drop the volume.

How The Artifact Supports The Paper

The artifact is submitted for and is awarded the Available and Functional badges.

The reviewers are able to:

build the artifact following the instructions
create a volume
use put/get operations to store a file and retrieve it
generate the parity
run degraded read and recovery

It supports the paper by showing that the proposed optimal erasure code repair is functional.

Additional Notes and Resources

In our test environment, a few reviewers saw the messages “Not responding, begin to ping.” The current prototype may be opening too many connections.