What is embedded Linux? Part I | Ubuntu

Intuitively, an embedded Linux system simply denotes an embedded system running on the Linux kernel. Let us focus on the remaining two pieces. Blog Overview InternetofThings Desktop CloudandServer Topics Design Juju MAAS Robotics Snapcraft Presscentre Design Juju MAAS Robotics Snapcraft Yoursubmissionwassentsuccessfully!Close “Helloeverybodyoutthereusingminix–  I’mdoinga(free)operatingsystem(justahobby,won’tbebigandprofessionallikegnu)for386(486)ATclones. […]ItisNOTportable(uses386taskswitchingetc),anditprobablyneverwillsupportanythingotherthanAT-harddisks,asthat’sallIhave:-(.”[1] TheaboveisanexcerptfromLinusTorvalds’originalannouncementofwhatcametobeknownworldwideastheLinuxoperatingsystem(OS),datedAugust1991.Inhindsight,itisinconceivablymodestnowthatweareinamuchbetterpositiontoappreciatethefullrevolutionaryextentofhispost.Today,morethan96.4%ofthetop1millionserverapplicationsrunonLinux[2].Acrosspublicclouds,90%oftheworkloadsuseLinuxastheirOS,withUbuntubeingthemostpopularLinuxdistro[3],[4].Despitedebutingasageneral-purposeoperatingsystem(GPOS)forx86-basedhardware,Linuxmovedbeyondwebserversandhasseenwidespreadadoptionforembeddedsystemseversince. Thistwo-partblogseriesaimstoprovidethereaderwithabroadoverviewoftopicsspanningtheworldofLinux,embeddedsystemsandtheInternetofThings(IoT)ingeneral.InpartIofthisblogseries,we’llstartbytakingalookattheembeddedecosystem,followedbyanexplanationofLinux’sroleinit,andwillconcludebyexplainingtherationalebehindtheOSgrowingpopularityinembeddedsystems.InpartII,we’llfocusonthemostpressingchallengesfacingenterprisestodaywithintheembeddedspace.Let’sgetstarted. Theembeddedlandscape  Althoughappearinginmultipleshapesandforms,anembeddedsystemtypicallyperformsadedicatedfunction,isresource-constrainedandcomprisesaprocessingengine.Attheriskofover-simplifyingmatters,wecandelineatethreebroadcategoriesregardingthesizeofanembeddedLinuxsystem:[5] Small-sizedsystems,comprisingalow-poweredCPUwithatleast2MBofread-onlymemory(ROM)and4MBofrandom-accessmemory(RAM).Medium-sizedsystems,witharound32MBofROM,64MBofRAMandamedium-poweredCPU.Large-sizedembeddedsystems,withpowerfulCPUsandalargermemoryfootprint. Spanningvirtuallyallcategoriesofconsumerspending—fromautomotivetohomeenergymanagement—Linux’spresenceinembeddedsystemsisubiquitous.   [6] This,however,hasnotalwaysbeenthecase,asprogressinsemiconductortechnologyhassubstantiallyhelpedspurLinux’sadoptionintheembeddedworld.Severalreasonsaccountforsuchgrowth.Amongthose,flashmemorypriceshavedecreasedovertime,providingthenecessarymassstoragefortheLinuxfilesystem[7].Similarly,low-powersmall-footprintSystemonaChip(SoC)hardwareisincreasinglybecomingthedeveloper’spremierprocessorchoice.Asaconsequence,virtuallyeveryembeddedsystemiscapableofrunningLinux–anddoes! WhatisembeddedLinux? We’renowinabetterpositiontolookattheopeningquestion,“WhatisembeddedLinux?” Therearethreelevelsatwhichwecanattemptananswer: ThesystemThekernel(i.e.,thecoreoftheOS)Thedistro Thesystem Intuitively,anembeddedLinuxsystemsimplydenotesanembeddedsystemrunningontheLinuxkernel.Letusfocusontheremainingtwopieces. TheLinuxkernel Linusnevershippedan“embeddedversion”oftheLinuxkernel.Asanembeddeddeveloper,youmaynotrequireatailoredkernelforyoursystemandmightrelyonanofficialreleaseinstead.However,itisoftenthecasethatyoumayneedakernelconfiguredtosupportyourcustomhardware,asthekernelbuildconfigurationfoundinanembeddeddeviceusuallyvariesfromtheoneinaserverorworkstation. Thedistro(ordistribution) Thethirdperspectivetoconsideristhatofadistribution.Here,“distribution”isanumbrellatermusuallycomprisingsoftwarepackages,servicesandadevelopmentframeworkontopoftheOSitself.UbuntuCore,theflavourofUbuntuforembeddeddevices,isanexampleofanembeddedLinuxdistro. EmbeddedLinuxvsRTOS WhyuseembeddedLinux? Thenextquestionthatarisesis,whatmakesLinuxtheperfectcandidateforanembeddedsystem?Fromscalabilitytodevelopersupportandtooling,therearemyriadreasonswhythisistrue.Anin-depthdiscussionforeachrequiresitsownbook.Here,we’lllimitourselvestomentioningafewprominentones: HardwaresupportNetworkingModularityCommercialsupport Hardwaresupport Linuxrunson32and64-bitARM,x86,MIPS,andPowerPCarchitectures.Whereasa32-bitprocessoriscapableofstoring232(onebitiseithera0ora1,hencethereare2possiblecombinations)values,a64-bitprocessorcanstoremorememoryaddresses.Processorsbelow32-bitaren’tcapableofrunningLinux,rulingouttraditionalembeddedsystems.Foramorein-depthdiscussiononhardwaresupport,youcanchecktherichecosystemofplatformsforUbuntuCorehere. Networking We’reallwellawarethatnetworkingcapabilitiesareexpectedout-of-the-boxinmostconsumerproducts.Fortunately,Linuxsupportsarichstackofnetworkingprotocols.WhetheryourembeddedLinuxprojectrequiresWiFi,mobilebroadband(WWAN)orEthernetconnectivity,systemnetworkserviceslikeNetworkManageraresupportedonLinux.YoucaneasilyinstallNetworkManageronUbuntuCorebyfollowingthisguide. Modularity ThethirdreasonbehindLinux’sprevalenceinembeddedsystemsisitsmodularity.WithseveralsoftwarepackagescomingtogethertoformaLinuxOSstack,developerscancustomizeitforanypurpose.Forinstance,customisationoptionsforUbuntuCoreincludeconfigurationforbothhardwareandsoftware,andspecifickernels.  Commercialsupport AnothercrucialbutsometimesoverlookedconsiderationforchoosingLinuxforyourembeddedsystemsistheavailabilityofcommercialsupport. Freelyavailable,community-maintainedbuildsystemssuchasYoctoandBuildrootenabledeveloperstocreatecustomLinuxdistrosformosthardwarearchitectures.Unfortunately,thevariouschallengesthatcommunityprojectsdonotaddressareboundtosurfacewhenshippingembeddedLinuxinproduction.Thisgapis,however,readilyfilledbyembeddedLinuxvendorswhoprovideenterprise-gradesupportandexpertise,substantiallyreducingtimetomarket. It’snotonlyexpensiveforanenterprisetoprovideitsownsetoffixes,securitypatches,andhardwaretesting–it’salsodistractingfromitscorebusiness.Luckily,thekernelexpertsatCanonical,thecommercialsponsorofUbuntu,areheretohelp.Canonical’steambuilds,patchesandmaintainsUbuntuCoreforembeddeddevices. Ifyou’reinterested,afocusseddiscussiononthebenefitsanddisadvantagesawaitingembeddeddeveloperswhenrollingtheirownLinuxdistroversusrelyingonacommerciallysupportedsolutionisavailableinthiswebinarorthiswhitepaper. Conclusion Bynow,thereadersshouldfeelfamiliarwiththeroleplayedbyLinuxwithintheembeddedlandscape.InpartIofthistwo-partblogserieswesawhowLinux,withitswell-establishedpresenceamongserversandclouds,israpidlybecomingthede-factoOSfortheembeddedworld.ThereareobviousreasonstochooseLinuxforanembeddedsystem,fromhardwareandnetworkingprotocolsupporttoitsextensiveconfigurabilityandmodularity. YoucangainanappreciationofhowUbuntuCore,theembeddedflavourofthemostwidelydeployedserveroperatingsystemontheInternet[8],issettingnewstandardsforembeddedLinuxbybrowsingthroughitsdatasheet. InpartIIofthisblogseries,we’llarguehowdevelopersmustpaycloseattentiontotheissuesofsecurityandupdatabilityiftheyaretoreapthebenefitsoftheexplosiveIoTgrowth.Seeyouthere. IoTasaservice BringanIoTdevicetomarketfast.Focusonyourapps,wehandletherest.Canonicaloffershardwarebringup, appintegration,knowledgetransferandengineeringsupporttogetyourfirstdevicetomarket.Appstoreand securityupdatesguaranteed. GetyourIoTdevicetomarketfast › IoTappstore Buildaplatformecosystemforconnecteddevicestounlocknewavenuesforrevenuegeneration. Getasecure,hostedandmanagedmulti-tenantappstoreforyourIoTdevices. BuildyourIoTappecosystem › Selecttopicsyou'reinterestedin CloudandServer Desktop InternetofThings Robotics Tutorials Website: Name: Workemail:* IagreetoreceiveinformationaboutCanonical'sproductsandservices. Insubmittingthisform,IconfirmthatIhavereadandagreetoCanonical'sPrivacyNoticeandPrivacyPolicy. Subscribenow Relatedposts Embeddedsystems:theadventoftheInternetofThings–PartII Thisisthesecondpartofthetwo-partblogseriescoveringembeddedLinuxsystemsandthechallengesbroughtaboutbytheproliferationofInternetof... InternetofThingsandUbuntu:2021highlights Withrisingunitshipmentsandhardwarespending,2021willgointotherecordbooksasacriticalyearintheever-increasingadoptionofconnecteddevices.... CanonicalkeynoteatEmbeddedWorld2021:BoschRexrothachievescompleteIoTautomationwithUbuntuCore Thisyear,we’reexcitedtobesponsoringEmbeddedWorldonceagain.We’reparticularlythrilledtoinviteyoutothespeakerforumtomorrow,Fridaythe5th,...