zanhsieh / docker-storage-centos7-face-off

Docker 1.9.1 file IO testing raw vs loop lvm vs direct lvm

Docker Storage Centos 7 Face-off

Docker 1.9.1 file IO testing raw vs loop lvm vs direct lvm

Spec

• Intel(R) Xeon(R) CPU E5-2623 v3 @ 3.00GHz x2
• 16GB RAM
• 3 TB HDD
• LVM 10GB
• CentOS 7.1.1503
• Docker version 1.9.1, build a34a1d5
• iozone: 3.434 (Stable; go to http://www.iozone.org/ -> click "Stable tarball" under "Download Source")

How did I test

Raw machine test:

1. CentOS yum update
2. Yum install gcc, make
3. Follow this instruction (http://www.thegeekstuff.com/2011/05/iozone-examples/) download iozone current stable version and make the test (./iozone -a -b raw_data.xls)

Docker loopback / thin-lvm test:

1. Install Docker as official document (https://docs.docker.com/engine/installation/centos/) instructed

2. Modify daemon (/usr/lib/systemd/system/docker.service) to work around build image issue (moby/moby#17653; look at crosbymichael comment on Nov 11, 2015) and start docker daemon

3. Build c7perf image ("docker build -t c7perf --rm=true .") based on https://github.com/jeremyeder/docker-performance/blob/master/Dockerfiles/Dockerfile. Note that Dockerfile should be place next to iozone_3_434 directory (see Dockerfile enclosed)

4. Create /results directory, run c7perf docker image, and do test:

    # mkdir -p /results
    # chcon -Rt svirt_sandbox_file_t /results
    # docker run -it -v /results:/results c7perf bash
    # cd /root/src/current
    # ./iozone -a -b /results/loop_data.xls
   

Docker direct LVM test:

1. Dump the image we just build (c7perf and centos) with Docker save (https://docs.docker.com/engine/reference/commandline/save/) to tar file, and save to somewhere

2. Stop docker service

3. Follow instruction on docker official site (https://docs.docker.com/engine/userguide/storagedriver/device-mapper-driver/) to make the change

4. For change daemon part, the line should look like this:

    ExecStart=/usr/bin/docker daemon --storage-driver=devicemapper --storage-opt dm.datadev=/dev/vg-docker/data --storage-opt dm.metadatadev=/dev/vg-docker/metadata -H fd://
   

5. Start Docker daemon and load images back (https://docs.docker.com/engine/reference/commandline/load/)

6. Repeat Docker loopback section to test:

    # docker run -it -v /results:/results c7perf bash
    # cd /root/src/current
    # ./iozone -a -b /results/directlvm_data.xls
   

Test Result

See the excel file in this project

Conclusion?

No straightforward conclusion. It depends on the scenario you use Docker.