本文將討論它是如何工作的
關於 Docker 的常見問題及其解決方案
主要特點
- 使用獨立的核心,從而提供網絡、內存和 I/O 隔離,可以強制使用基於虛擬化擴展的硬件隔離
- 支持行業標準,包括 OCI(容器格式)、Kubernetes CRI
- 常規 Linux 容器的一致性能,增強隔離性,而無需常規虛擬機的性能開銷
- 無需在成熟的虛擬機內運行容器,通用接口簡化了集成和啟動
安裝
有
這一點很重要:Kata Containers 工作僅在硬件上受支持,虛擬化轉發並不總是有效,而且 需要sse4.1支持 來自處理器。
安裝 Kata 容器非常簡單:
安裝用於使用存儲庫的實用程序:
# yum -y install yum-utils
禁用Selinux(配置更正確,但為了簡單起見我禁用它):
# setenforce 0
# sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config
我們連接存儲庫並執行安裝
# source /etc/os-release
# ARCH=$(arch)
# BRANCH="${BRANCH:-stable-1.10}"
# yum-config-manager --add-repo "http://download.opensuse.org/repositories/home:/katacontainers:/releases:/${ARCH}:/${BRANCH}/CentOS_${VERSION_ID}/home:katacontainers:releases:${ARCH}:${BRANCH}.repo"
# yum -y install kata-runtime kata-proxy kata-shim
調整
我將設置與 docker 一起工作,它的安裝是典型的,我不會更詳細地描述它:
# rpm -qa | grep docker
docker-ce-cli-19.03.6-3.el7.x86_64
docker-ce-19.03.6-3.el7.x86_64
# docker -v
Docker version 19.03.6, build 369ce74a3c
我們對 daemon.json 進行更改:
# cat <<EOF > /etc/docker/daemon.json
{
"default-runtime": "kata-runtime",
"runtimes": {
"kata-runtime": {
"path": "/usr/bin/kata-runtime"
}
}
}
EOF
重新啟動碼頭工人:
# service docker restart
功能測試
如果在重新啟動 docker 之前啟動容器,您可以看到 uname 將給出主系統上運行的內核版本:
# docker run busybox uname -a
Linux 19efd7188d06 3.10.0-1062.12.1.el7.x86_64 #1 SMP Tue Feb 4 23:02:59 UTC 2020 x86_64 GNU/Linux
重啟後,內核版本如下:
# docker run busybox uname -a
Linux 9dd1f30fe9d4 4.19.86-5.container #1 SMP Sat Feb 22 01:53:14 UTC 2020 x86_64 GNU/Linux
更多團隊!
# time docker run busybox mount
kataShared on / type 9p (rw,dirsync,nodev,relatime,mmap,access=client,trans=virtio)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev type tmpfs (rw,nosuid,size=65536k,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=666)
sysfs on /sys type sysfs (ro,nosuid,nodev,noexec,relatime)
tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,relatime,mode=755)
cgroup on /sys/fs/cgroup/systemd type cgroup (ro,nosuid,nodev,noexec,relatime,xattr,name=systemd)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (ro,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/blkio type cgroup (ro,nosuid,nodev,noexec,relatime,blkio)
cgroup on /sys/fs/cgroup/memory type cgroup (ro,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/devices type cgroup (ro,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/perf_event type cgroup (ro,nosuid,nodev,noexec,relatime,perf_event)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (ro,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/freezer type cgroup (ro,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/pids type cgroup (ro,nosuid,nodev,noexec,relatime,pids)
cgroup on /sys/fs/cgroup/cpuset type cgroup (ro,nosuid,nodev,noexec,relatime,cpuset)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
shm on /dev/shm type tmpfs (rw,nosuid,nodev,noexec,relatime,size=65536k)
kataShared on /etc/resolv.conf type 9p (rw,dirsync,nodev,relatime,mmap,access=client,trans=virtio)
kataShared on /etc/hostname type 9p (rw,dirsync,nodev,relatime,mmap,access=client,trans=virtio)
kataShared on /etc/hosts type 9p (rw,dirsync,nodev,relatime,mmap,access=client,trans=virtio)
proc on /proc/bus type proc (ro,relatime)
proc on /proc/fs type proc (ro,relatime)
proc on /proc/irq type proc (ro,relatime)
proc on /proc/sys type proc (ro,relatime)
tmpfs on /proc/acpi type tmpfs (ro,relatime)
tmpfs on /proc/timer_list type tmpfs (rw,nosuid,size=65536k,mode=755)
tmpfs on /sys/firmware type tmpfs (ro,relatime)
real 0m2.381s
user 0m0.066s
sys 0m0.039s
# time docker run busybox free -m
total used free shared buff/cache available
Mem: 1993 30 1962 0 1 1946
Swap: 0 0 0
real 0m3.297s
user 0m0.086s
sys 0m0.050s
快速負載測試
為了評估虛擬化帶來的損失 - 我運行 sysbench,作為主要示例
使用 Docker+containerd 運行 sysbench
處理器測試
sysbench 1.0: multi-threaded system evaluation benchmark
Running the test with following options:
Number of threads: 1
Initializing random number generator from current time
Prime numbers limit: 20000
Initializing worker threads...
Threads started!
General statistics:
total time: 36.7335s
total number of events: 10000
total time taken by event execution: 36.7173s
response time:
min: 3.43ms
avg: 3.67ms
max: 8.34ms
approx. 95 percentile: 3.79ms
Threads fairness:
events (avg/stddev): 10000.0000/0.00
execution time (avg/stddev): 36.7173/0.00
內存測試
sysbench 1.0: multi-threaded system evaluation benchmark
Running the test with following options:
Number of threads: 1
Initializing random number generator from current time
Initializing worker threads...
Threads started!
Operations performed: 104857600 (2172673.64 ops/sec)
102400.00 MiB transferred (2121.75 MiB/sec)
General statistics:
total time: 48.2620s
total number of events: 104857600
total time taken by event execution: 17.4161s
response time:
min: 0.00ms
avg: 0.00ms
max: 0.17ms
approx. 95 percentile: 0.00ms
Threads fairness:
events (avg/stddev): 104857600.0000/0.00
execution time (avg/stddev): 17.4161/0.00
使用 Docker+Kata 容器運行 sysbench
處理器測試
sysbench 1.0: multi-threaded system evaluation benchmark
Running the test with following options:
Number of threads: 1
Initializing random number generator from current time
Prime numbers limit: 20000
Initializing worker threads...
Threads started!
General statistics:
total time: 36.5747s
total number of events: 10000
total time taken by event execution: 36.5594s
response time:
min: 3.43ms
avg: 3.66ms
max: 4.93ms
approx. 95 percentile: 3.77ms
Threads fairness:
events (avg/stddev): 10000.0000/0.00
execution time (avg/stddev): 36.5594/0.00
內存測試
sysbench 1.0: multi-threaded system evaluation benchmark
Running the test with following options:
Number of threads: 1
Initializing random number generator from current time
Initializing worker threads...
Threads started!
Operations performed: 104857600 (2450366.94 ops/sec)
102400.00 MiB transferred (2392.94 MiB/sec)
General statistics:
total time: 42.7926s
total number of events: 104857600
total time taken by event execution: 16.1512s
response time:
min: 0.00ms
avg: 0.00ms
max: 0.43ms
approx. 95 percentile: 0.00ms
Threads fairness:
events (avg/stddev): 104857600.0000/0.00
execution time (avg/stddev): 16.1512/0.00
原則上,情況已經很清楚了,但是最好運行幾次測試,刪除異常值並對結果進行平均,所以我還沒有做更多的測試。
發現
儘管事實上這樣的容器需要大約五到十倍的時間來啟動(使用containerd時類似命令的典型運行時間不到三分之一秒),但如果我們採用絕對啟動時間(有上面是示例,命令平均執行時間為三秒)。 好吧,對 CPU 和 RAM 的快速測試結果顯示幾乎相同的結果,這不能不令人高興,特別是考慮到使用 kvm 這樣運行良好的機制提供隔離。
公告
這篇文章是一篇評論,但它讓您有機會感受另類運行時。 許多應用領域都沒有涵蓋,例如,該網站描述了在 Kata 容器之上運行 Kubernetes 的能力。 此外,您還可以運行一系列測試,重點關注查找安全問題、設置限制和其他有趣的事情。
我請求所有閱讀並回顧此處的人參與這項調查,該主題的未來出版物將取決於該調查。
只有註冊用戶才能參與調查。
我應該繼續發表有關 Kata Containers 的文章嗎?
-
企業排放佔全球 80,0%是的,多寫點!28
-
企業排放佔全球 20,0%不,不要……7
35 位用戶投票。 7 名用戶棄權。
來源: www.habr.com