Monitoring Docker with Mackerel Docker meetup Tokyo #3, 2014-07-04 Hatena Co., Ltd. Shinji Tanaka @stanaka 

Agenda • Monitoring Docker • Docker Patterns & Deployment • Monitoring Docker with Mackerel 

1 Monitoring Docker 

DockerͷϞχλϦϯάͷجຊ • cgroupͷ࡞๏ʹै͏ • ίϯςφଆ͔Β͸ɺϗετશମ͔͠ ݟ͑ͳ͍ • /proc/loadavg,  /proc/stat 

ϗετଆ͔ΒͷϞχλϦϯά • cgroupͷϨϙʔτΛར༻ • /sys/fs/cgroup/
          {cpuacct,  memory}   • ଞʹblkio,  cpu,  devicesͳͲͷα ϒγεςϜ͕͋Δ(֤छ੍ݶͳͲͷ੍ ޚ༻) VCVOUV
ͷ৔߹
 LFSOFM
HFOFSJD

EPDLFS
 

CPU࢖༻཰ • /sys/fs/cgroup/cpuacct/docker/{ίϯςφID}/cpuacct.stat ! ! ! • user … ϢʔβʔϞʔυͷCPU ࣌ؒ • system … γεςϜϞʔυͷCPU ࣌ؒ • CPU࣌ؒͷ୯Ґ: USER_HZ (σϑΥϧτ͸10ms) user  480   system  116 

cpuacctͷଞͷࢦඪ • cpuacct.usage: ૯CPU࣌ؒ (φϊඵ)
 echo 0 > /cgroup/cpuacct/cpuacct.usage 
 ͰϦηοτ • cpuacct.usage_percpu: ֤CPUͷCPU ࣌ؒ (φϊඵ) 

ϝϞϦ࢖༻཰ • /sys/fs/cgroup/memory/docker/{ίϯςφID}/memory.stat cache  761856   rss  25681920   rss_huge  0   mapped_file  16384   pgpgin  12569   …   total_cache  761856   total_rss  25681920   …   ͍ΘΏΔ344

STT

NBQQFE@pMF 

memory.statৄࡉ • cache   • rss   • mapped_file   • pgpgin   • pgpgout   • swap   • active_anon   • inactive_anon   • active_file   • inactive_file   • unevictable   • hierarchical_memory _limit   • hierarchical_memsw   • total_͸ࢠάϧʔϓΛ ؚΉ஋ ৄࡉ
IUUQTXXXLFSOFMPSHEPD%PDVNFOUBUJPODHSPVQTNFNPSZUYU 

memoryؔ࿈(ͦͷଞ) memory.usage_in_bytes ϝϞϦ࢖༻ྔ memory.memsw.usage_in_bytes ϝϞϦ࢖༻ྔͱεϫοϓྖҬͷ࿨ memory.max_usage_in_bytes ϝϞϦ࠷େ࢖༻ྔ memory.memsw.max_usage_in_bytes εϫοϓ࠷େ࢖༻ྔ memory.limit_in_bytes ϝϞϦͷ੍ݶ஋ memory.memsw.limit_in_bytes ϝϞϦͱεϫοϓ੍ݶ஋ memory.failcnt ϝϞϦ੍ݶ஋ʹୡͨ͠ճ਺ memory.memsw.failcnt ϝϞϦ੍ݶ஋ʹୡͨ͠ճ਺ 

ڞ௨Ϩϙʔτ • tasks ࣮ߦதͷϓϩηεͷҰཡ(PID) • cgroup.procs ࣮ߦதͷεϨουάϧʔϓͷҰཡ(TGID) %  cat  /sys/fs/cgroup/memory/docker/…./cgroup.procs   31218   31307   %  ps  aux  |  egrep  '(31218|31307)'   root          31218    0.0    0.0      4408      164  ?                Ss      13:15      0:00  /bin/sh  -­‐ c  rackup  -­‐p4567   root          31307    0.0    5.2  281364  26336  ?                Sl      13:15      0:06  ruby1.9.1   /usr/local/bin/rackup  -­‐p4567 

2 Docker Patterns (with Docker Hub) & Deployment 

ϗετͱίϯςφͷؔ܎ • 1:n • CIαʔόɾ։ൃαʔόͳͲ • 1:1 • ϓϩμΫγϣϯ؀ڥͳͲ 

Pattern 1:n • CIαʔόɾ։ൃαʔό • ίϯςφԾ૝Խ؀ڥΛଟ਺ಈ࡞ • ಠཱͨ͠؀ڥ • ىಈఀࢭ͕ߴ଎ • Ϧιʔεͷڞ༗ʹΑΔޮ཰Խ 

Pattern 1:1 • ίϯςφԾ૝؀ڥΛҰͭͷΈಈ࡞ • ϦιʔεΛಠ઎ • ؀ڥߏங໘ʹಛԽ • ϓϩμΫγϣϯ؀ڥʹ߹͏ • AWS BeanstalkͷDocker support 

Deployment with Docker Hub 

Deployment (JU)VC %PDLFS
)VC IVCPU 

GitHub 

Docker Hub 

Automated Build 

Build Success 

Build Failed 

Webhook from Docker Hub {        "push_data":{              "pushed_at":1385141110,              "images":[                    "imagehash1"            ],              "pusher":"username"        },        "repository":{              "status":"Active",              "description":"my  docker  repo  that  does  cool  things",              "is_trusted":false,              "full_description":"This  is  my  full  description",              "repo_url":"https://registry.hub.docker.com/u/username/reponame/", 

hubot • νϟοτπʔϧͰσϓϩΠ • Build௨஌ ! • σϓϩΠ࣮ߦ 

3 Monitoring Docker with Mackerel 

Mackerel https://mackerel.io/ 

Mackerelʢ೔ຊޠͰḉʣ • αʔό؅ཧπʔϧ as a Service • લ਎: ͸ͯͳͷࣾ಺πʔϧ 

ಛ௃ • ʮ໾ׂʯʹΑΔϗετ܈ͷ؅ཧ • ΤʔδΣϯτʹΑΔϦιʔε؂ࢹ • API ʹΑΔ؅ཧ ϩ ʔ ϧ 

αʔϏεͱϩʔϧ • αʔϏε • ͞·͟·ͳϗετ͕ڠௐ • Hatena-Bookmark, Hatena-Blog, … • ϗετ܈Λ໾ׂͰ·ͱΊΔ = ϩʔϧ • app, db, … 

ϩʔϧຖͷάϥϑͰՄࢹԽ 

mackerel-agent • Go Ͱॻ͔ΕͨެࣜΤʔδΣϯτ • Linux αϙʔτ (CentOS 5/6, Debian 6/7) • ϗετεϖοΫͱϝτϦοΫΛऩू mackerelio/mackerel-agent 

αʔϏεɾϩʔϧͷࢦఆ • agentͷઃఆ͔ΒαʔϏεɾϩʔϧΛ ࢦఆ #  mackerel-­‐agent.conf   roles  =  [  “Mackerel:db”,  …  ] 

agent: ΧελϜϝτϦοΫ • Sensu ϓϥάΠϯޓ׵ͷग़ྗ
 ʢλϒ۠੾Γʣ %  ~/.mackerel-­‐agent/plugins/chrome-­‐tabs-­‐count.sh   browser.tabs.count            9              1403153173   browser.tabs.works            7              1403153173 

mackerel-docker • ϗετଆ͔ΒDockerίϯςφΛϞχλϦϯά ! • mackerel-agentͷઃఆ IUUQTHJUIVCDPNTUBOBLBNBDLFSFMEPDLFS %  cat  mackerel-­‐agent.conf
 [plugin.metrics.docker]
 command  =  "ruby  /home/stanaka/git/mackerel-­‐docker/mackerel-­‐ docker.rb" 

Dockerίϯςφ΁ͷ૊ࠐΈ • Dockerfile ! ! ! ! • Dockerίϯςφͷىಈ CMD  echo  APIKEY=\"$APIKEY\"  >  /etc/default/mackerel-­‐agent  
 &&  echo  OTHER_OPTS="-­‐role=sample:${ROLE:-­‐app2}"  >>  /etc/default/mackerel-­‐ agent  
 &&  /etc/init.d/mackerel-­‐agent  start  
 &&  env  MACKEREL_APIKEY=$APIKEY  mkr  host  status  -­‐-­‐host-­‐id  `cat  /var/lib/ mackerel-­‐agent/id`  -­‐-­‐status  working  
 &&  rackup  -­‐p4567 docker  run  -­‐e  “APIKEY=……”  stanaka/meetup 

Docker pluginʹΑΔϞχλϦϯά 

DockerίϯςφͷCPUάϥϑ 

Blue-green DeploymentରԠ • ϩʔϧ୯ҐͰͷՄࢹԽ • ୀ໾ࡁΈίϯςφͷάϥϑ΋อ࣋ Deployment 

Q & A