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Inside the PostgreS QL Project Infrastructure S lide: 1

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Dave Page, 25th March 2010

Ins ide the Pos tg reS QL Projec t Infras truc ture

Dave PagePostgreS QL Core Team

S enior S oftware Architect, EnterpriseDB

S lide: 2Dave Page, 25th March 2010 Inside the PostgreS QL Project Infrastructure

In the beginning...

Date: Tue, 23 Apr 1996 16:06:10 -0400 (EDT) From: "Marc G. Fournier" <[email protected]> Subject: Re: [PG95]: postgres95 TODO list posted on the web To: Chad Robinson <[email protected]> cc: Jolly Chen <[email protected]>, [email protected]

…

...

If it helps, I’d be willing to setup a cvs database, including appropriate accounts for a core few developers that patches can go through.

From there, it wouldn’t be too hard to do a weekly "distribution" that is ftpable.

I don’t know enough about the server backend to offer much more then that :(\


The first server

Hosted in Toronto, Canada


Early services

• Mailing lists

• CVS repository

• FTP site


14 Years later...

• 20+ Physical servers

• 35+ Virtual Machines

• Hosted in:– France– Panama C ity– Austria– Canada– US A (4 independent locations)


Current services

• FTP site• Website• S ource control – CVS and GIT• Mailing lists• Wiki• Mailing list archives• Website/archives search• pgFoundry• Commitfest management server• Buildfarm and Hudson servers• Development servers… and more!


OS “zoo”

• Primarily using FreeBS D jails:– Easy to backup– Easy to relocate– Per-function jails

• Also running:– Ubuntu– S lackware– CentOS– Windows


Problems

• Little FreeBS D experience in the community.

• FreeBS D Ports are hard to upgrade, especially with lots of jails.

• Hosting companies don't tend to like FreeBS D – and we can't be too picky!

• No centralised management or deployment.


New infrastructure

• Runs Debian virtual machines under KVM on Debian hosts.

• Pre-built packages setup base hosts and VMs.

• Management system automates:– VM creation and configuration.– Addition and removal of user accounts and S S H keys.– Package installation and upgrades.– Detection of unexpected user accounts or unauthorised services.– S etup and configuration of Nagios and Munin monitoring.– Auto-backup configuration


Monitoring

• Nagios

• Munin

• S mokeping

• Auto-backup

• Google Analytics


Nagios

• 64 Hosts

• 514 S ervices

• S ervice checks include:– S ervice availability – NTP, S S H, HTTP, FTP, RS YNC etc.– Utilisation – disk usage, logged in users, processes, mail queue– Management – software update availability– “Our stuff” - buildfarm status, search indexer, database backups


Nagios


Munin

• Monitors resource trends:– Disk usage– Network utilisation– Processes– S endmail/Postfix stats– CPU/Memory utilisation– Apache stats


Munin

• CPU usage – postgresql01.managed.contegix.com


S mokeping

• Monitors network latency to various hosts from the Conova Communications data centre in S alzburg, Austria


Auto-backup

• Automatically backs up changes to key configuration files to S ubversion.

– Gives us a simple backup of config files– Allows us to trace the history of changes to a file

• Alerts the sysadmins to changes to monitored files

– Helps us see what the other team members are doing– Acts as a simple Intrusion Detection System


Google Analytics

• Monitors website utilisation.

• Helps us understand how the website is used.

• Can be hampered by disabled scripting support in browsers, common with computer geeks!


Google Analytics


FTP S ite

• Primary site: ftp.postgresql.org

• 62 regional mirrors in 39 countries

• Mirrors may also serve content via:– HTTP (supported)– RS YNC (unsupported)

• Content includes main FTP site, and pgFoundry downloads


FTP Mirror monitoring

• All mirrors are checked daily by the 'mirrorbot'

• The mirrorbot checks that content is up to date:

– Fresh mirrors have a DNS hostname, e.g. ftp.uk.postgresql.org– Fresh mirrors are listed on the website for users to choose

• Out of date or broken mirrors:

– Are automatically removed from the website and DNS .– Are reported to their maintainers via email.– Are automatically purged from the system if un-fixed.


Website infrastructure

• Developed following the great 8.0 S lashdotting incident.

• Capable of handling high-load scenarios on release days..

• Minimised points of failure.


wwwmaster.postgresql.org

• Dynamic, master server.

• Runs custom-built PHP framework for:– S tatic page rendering (general content)– Dynamic page rendering (docs, news, events etc)– Form processing

• Dynamic content stored in PostgreS QL.

• S tatic version of content generated hourly by a spider, and pushed via RS YNC to the static servers.

• Users redirected back to static servers where possible.


www.postgresql.org

• S tatic, slave servers

• S erve HTML, CS S , images and files such as PDFs.

• Currently 2 servers.

• Geographically diverse.

• Round-robin load balanced via DNS .

• Monitoring system dynamically removes servers from DNS within minutes of a failure.


Website problems

• PHP framework is complex, and understood by few.

• Adding new dynamic content can require significant effort to build administration pages.

• The framework includes lots of features and code we thought we needed, but then never used.

• S pider can take hours to process the entire site.

• S pidering the site is very inefficient.


New website infrastructure

• S limmed down and vastly simplified framework, built using Django and Python.

• Django's administration module makes it easy to add and manage content.

• S pider and static slaves will be replaced with Varnish cache servers:– Pages dynamically cached from wwwmaster on first request.– Last available content served if wwwmaster goes down.– Cache invalidation of individual or groups of pages as changed

on wwwmaster.


Questions?

Thank you.