Ovaj članak govori o tome kako to funkcionira
Već o uobičajenim problemima s Dockerom i njihovim rješenjima
Ključne značajke
- Radeći s odvojenom jezgrom, čime se osigurava mreža, memorija i I/O izolacija, moguće je prisilno koristiti hardversku izolaciju temeljenu na virtualizacijskim proširenjima
- Podrška za industrijske standarde uključujući OCI (format spremnika), Kubernetes CRI
- Konzistentna izvedba uobičajenih Linux spremnika, povećana izolacija bez opterećenja performansi običnih VM-ova
- Uklonite potrebu za pokretanjem spremnika unutar punopravnih virtualnih strojeva, generička sučelja pojednostavljuju integraciju i pokretanje
Instalacija
Tu je
To je važno: Rad Kata kontejnera podržan je samo na hardveru, virtualizacijsko prosljeđivanje također ne radi uvijek potrebna podrška za sse4.1 od procesora.
Instaliranje Kata kontejnera je vrlo jednostavno:
Instalirajte pomoćne programe za rad sa spremištima:
# yum -y install yum-utils
Onemogući Selinux (ispravnije je konfigurirati, ali zbog jednostavnosti ga onemogućim):
# setenforce 0
# sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config
Spajamo repozitorij i izvodimo instalaciju
# source /etc/os-release
# ARCH=$(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
podešavanje
Postavit ću se za rad s dockerom, njegova instalacija je tipična, neću je detaljnije opisivati:
# 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
Mi mijenjamo daemon.json:
# cat <<EOF > /etc/docker/daemon.json
{
"default-runtime": "kata-runtime",
"runtimes": {
"kata-runtime": {
"path": "/usr/bin/kata-runtime"
}
}
}
EOF
Ponovno pokreni docker:
# service docker restart
Provjera funkcionalnosti
Ako pokrenete spremnik prije ponovnog pokretanja dockera, možete vidjeti da će uname dati verziju kernela koji radi na glavnom sustavu:
# 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
Nakon ponovnog pokretanja, verzija kernela izgleda ovako:
# 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
Više timova!
# 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
Brzo testiranje opterećenja
Za procjenu gubitaka od virtualizacije - pokrećem sysbench, kao glavne primjere
Pokretanje sysbencha pomoću Docker+container
Test procesora
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
RAM test
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
Pokretanje sysbencha pomoću Docker+Kata kontejnera
Test procesora
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
RAM test
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
U principu, situacija je već jasna, ali je optimalnije provesti testove nekoliko puta, uklanjajući outliere i usrednjavajući rezultate, tako da još ne radim više testova.
Zaključci
Unatoč činjenici da takvim spremnicima treba oko pet do deset puta više vremena za pokretanje (tipično vrijeme izvođenja sličnih naredbi pri korištenju spremnika je manje od trećine sekunde), oni i dalje rade prilično brzo ako uzmemo apsolutno vrijeme pokretanja (tamo su primjeri iznad, naredbe se izvode u prosjeku za tri sekunde). Pa, rezultati brzog testa CPU-a i RAM-a pokazuju gotovo iste rezultate, što ne može nego veseliti, posebno u svjetlu činjenice da je izolacija osigurana pomoću tako dobro upravljanog mehanizma kao što je kvm.
Obavijest
Članak je pregled, ali vam daje priliku da osjetite alternativno vrijeme izvođenja. Mnoga područja primjene nisu pokrivena, na primjer, stranica opisuje mogućnost pokretanja Kubernetesa povrh Kata kontejnera. Osim toga, također možete pokrenuti niz testova usmjerenih na pronalaženje sigurnosnih problema, postavljanje ograničenja i druge zanimljive stvari.
Molim sve koji su ovdje čitali i premotavali da sudjeluju u anketi o kojoj će ovisiti buduće objave na ovu temu.
U anketi mogu sudjelovati samo registrirani korisnici.
Trebam li nastaviti objavljivati članke o Kata kontejnerima?
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80,0%Da, napiši više!28
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20,0%Ne, nemoj…7
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Izvor: www.habr.com