1dd7473078
Replace the previous code that allocated each tracker individually with one large allocation per queue pair. struct nvme_tracker is now explicitly padded to reach exactly 4096 bytes to allow normal array indexing to work correctly while maintaining the alignment requirement that ensures each tracker's PRP list does not cross a page boundary. This also allows removal of the act_tr array, since the tr array can be indexed directly now, and each tracker can store its own active state. Change-Id: Ia7c51735b96594d12f7f478cefcc4aedc84207ad Signed-off-by: Daniel Verkamp <daniel.verkamp@intel.com>
Storage Performance Development Kit
The Storage Performance Development Kit (SPDK) provides a set of tools and libraries for writing high performance, scalable, user-mode storage applications. It achieves high performance by moving all of the necessary drivers into userspace and operating in a polled mode instead of relying on interrupts, which avoids kernel context switches and eliminates interrupt handling overhead.
The development kit currently includes:
- NVMe driver
- I/OAT (DMA engine) driver
Documentation
Doxygen API documentation is available, as well as a Porting Guide for porting SPDK to different frameworks and operating systems.
Many examples are available in the examples directory.
Prerequisites
To build SPDK, some dependencies must be installed.
Fedora/CentOS:
sudo dnf install -y gcc libpciaccess-devel CUnit-devel libaio-devel
Ubuntu/Debian:
sudo apt-get install -y gcc libpciaccess-dev make libcunit1-dev libaio-dev
FreeBSD:
- gcc
- libpciaccess
- gmake
- cunit
Additionally, DPDK is required.
1) cd /path/to/spdk
2) wget http://dpdk.org/browse/dpdk/snapshot/dpdk-2.2.0.tar.gz
3) tar xfz dpdk-2.2.0.tar.gz
Linux:
4) (cd dpdk-2.2.0 && make install T=x86_64-native-linuxapp-gcc DESTDIR=.)
FreeBSD:
4) (cd dpdk-2.2.0 && gmake install T=x86_64-native-bsdapp-clang DESTDIR=.)
Building
Once the prerequisites are installed, run 'make' within the SPDK directory to build the SPDK libraries and examples.
make DPDK_DIR=/path/to/dpdk
If you followed the instructions above for building DPDK:
Linux:
make DPDK_DIR=./dpdk-2.2.0/x86_64-native-linuxapp-gcc
FreeBSD:
gmake DPDK_DIR=./dpdk-2.2.0/x86_64-native-bsdapp-clang
Hugepages and Device Binding
Before running an SPDK application, some hugepages must be allocated and any NVMe and I/OAT devices must be unbound from the native kernel drivers. SPDK includes scripts to automate this process on both Linux and FreeBSD. Both of these scripts should be run as root.
1) scripts/configure_hugepages.sh
2) scripts/setup.sh
Examples
Example code is located in the examples directory. The examples are compiled automatically as part of the build process. Simply call any of the examples with no arguments to see the help output. You'll likely need to run the examples as a privileged user (root) unless you've done additional configuration to grant your user permission to allocate huge pages and map devices through vfio.