BIZA

Design of Self-Governing Block-Interface ZNS AFA for Endurance and Performance!

Introduction

BIZA is a self-governing ZNS AFA that can benefit from the openness of ZNS interface whilst exposing the user-friendly block interface to upper-layer applications.

We implement BIZA as a pluggable device mapper in Linux kernel (see drivers/md/dm-biza*). Expectedly, you can install it directly using insmod command. However, the support of ZRWA feature is still incomplete in the current kernel version. Therefore, we compromise to make some intrusive modifications to the block layer and NVMe driver, which complicates the installation process.

For fast deployment, we choose to release BIZA and Linux kernel as a whole. We've included all the necessary kernel codes for running BIZA in this repository. Therefore, you can deploy BIZA by simply compiling and installing this repository.

This repository is developed on Linux kernel v5.15.0. We've also integrated RAIZN and dm-zap (with some improvement) in this repository for comparison.

Please consider citing our paper at SOSP 2024 if you use BIZA. The BibTex is shown below:

Coming soon...

Environment

Special Hardware: Our tests require at least 4 WD ZN540 SSDs. BIZA would support other types of ZNS SSDs (but we have not validated this for the lack of hardware from other vendors).

Note: Kernel modification is a malicious and destructive operation. Potential bugs may cause system crashes. Therefore, we strongly recommend you use BIZA on a virtual machine (VM).

The following is an example to run VM with ZNS SSD:

OSIMG=path/to/your/os/img

sudo qemu-system-x86_64 \
    -enable-kvm \
    -cpu host \
    -smp 32 \
    -m 128G \
    -device virtio-scsi-pci,id=scsi0 \
    -device scsi-hd,drive=hd0 \
    -drive file=$OSIMG,if=none,aio=native,cache=none,format=qcow2,id=hd0 \
    -device vfio-pci,host=0000:18:00.0,multifunction=on \
    -device vfio-pci,host=0000:19:00.0,multifunction=on \
    -device vfio-pci,host=0000:51:00.0,multifunction=on \
    -device vfio-pci,host=0000:52:00.0,multifunction=on \
    -net user,hostfwd=tcp::5555-:22 \
    -net nic,model=virtio \
    -nographic

Here, we use vfio-pci for PCIe passthrough. Related tutorials can be found here.

Setup

Note: The current scripts are developed for Ubuntu 22.04 LTS. Porting to other OS may require some script modifications.

1. Clone BIZA from Github:

mkdir biza && cd biza
mkdir build
git clone https://github.com/ChaseLab-PKU/BIZA.git
mv BIZA codes && cd codes

2. Install the dependencies:

sudo apt update && sudo apt upgrade
sudo apt-get install git fakeroot build-essential ncurses-dev xz-utils libssl-dev bc flex libelf-dev bison libc6-dev liblz4-tool

3. Compile and Install BIZA:

In fact, you can compile and install BIZA with the same way as a common Linux kernel. Lots of guidances can be found online. For example:

make -j $(nproc) deb-pkg	# really time-consuming
cd ..
mv linux-* build/
cd build
sudo dpkg -i *.deb

Afterward, when you reboot your machine, you can choose the new kernel that contains BIZA.

Run

When you've opened your server with the new kernel, you can create BIZA target with bash command. Here is an example to create BIZA with 4 ZNS SSDs as RAID 5:

echo "0 409600 biza 4 1 64 /dev/nvme0n2 /dev/nvme1n2 /dev/nvme2n2 /dev/nvme3n2" | sudo dmsetup create biza0
# /dev/nvme*n2 are your ZNS SSDs.

If your DRAM capacity is not enough, please divide your ZNS SSD into smaller namespaces in advance, see here.

Afterward, you can find a new device named /dev/dm-* with lsblk command. Just use it as a common block device!