spice-协议简介课件

SPICE:AnOpenRemoteComputingSolutionPresenter:ArnonGilboaProjectLeader:YanivKamayRedHatIsraelSeptember4,2009AgendaWhySpice?ArchitectureSpiceOptimizationsFutureDevelopmentsQ&AWhySpice?OpenremotecomputingsolutionClientaccesstoremotemachinedisplay&devicesEmphasizeonvirtualmachinesenvironmentNoneedforguestnetworkingUserexperiencesimilartolocalmachineHighqualityvideo&audioOffloadintensiveCPU&GPUtaskstoclientSuitableforbothLAN&WANusageHowSpice?Transfergraphiccommands/objects(currently2D)OthersolutionsuseframebufferupdatesFill,copy,stretch,pathstroke,text,pointershapeetc.Generic&platform-independentLosslessimages,lossyvideo&audioARCHITECTURESpiceArchitectureDevices(QXL,VDIPort)GuestQEMU/KVMSpiceServer(libspice)SpiceClientClientHostSpiceAgentDrivers(QXL,VDIPort)SpiceProtocolGuestQEMU/KVMSpiceServer(libspice)SpiceClientClientDevicesHostSpiceAgentDriversGuestQEMU/KVMSpiceServer(libspice)SpiceClientClientHostSpiceProtocolClient-servercommunicationSetofmessagesforinteractionwithremotedevicesGraphiccommands,keyboard&mouseevents,audiostreamsetc.Secureauthentication–ticketing(OTP)withexpirationConnectionestablishmentandcontrol(e.g.,migration)Flowcontrolusingwindow-acksClient-ServerCommunication:ChannelsClient&servercommunicateviachannelsTCPconnectionsEachChanneldedicatedtoaspecifictypeofdataChannelcanbesecuredusingSSLorunsecuredIntheclient,eachchannelhasadedicatedthreadDifferentQoScanbegivenperchannelChannelsMain-controlandconfigurationandagentcommunicationDisplay-handlesgraphiccommands,imagesandvideostreamsInputs-keyboardandmouseinputsCursor-pointerdeviceposition,visibilityandcursorshapePlayback-audioreceivedfromtheservertobeplayedbytheclientRecord-audiocaptureontheclientsideSpiceServerGuestQEMU/KVMSpiceServer(libspice)SpiceClientClientDevicesHostSpiceAgentDriversGuestQEMU/KVMSpiceServer(libspice)SpiceClientClientDevicesHostSpiceServer–apluggablelibraryVirtualDeviceInterface(VDI)DefinesasetofinterfacesPublishesvirtualdevices(e.g.,display,keyboard,mouse)Enablesinteractionwithdeviceslibspice–theserver,aVDI-pluggablelibraryInteractswithVDIhostapplication(e.g.,QEMU)CommunicateswithclientusingSpiceprotocolSpiceServer–InterfacesQEMUPlaybackChannelPlaybackInterfaceRecordChannelRecordInterfaceMainChannelAgentInterfaceInputsChannelkbd,mouse&tabletInterfacesDispatcherWorkerThreadDisplayChannelCursorChannelQXLInterfaceSpiceServerSpiceServer–GraphicCommandsProcessing(1)GraphicCommandsTreeContainsthesetofcommands,whoseexecutionwillreproducethedisplaycontentUsedtooptimizecommandstransmissiontotheclientbydroppingcommandshiddenbyothersCommandPipeCommandstobesenttotheclient,forupdatingitsdisplaySpiceServer–GraphicCommandsProcessing(2)CommandRing(IN)ExpectedDisplayGraphicCommandTreeCommandPipe(OUT)SpiceServer–GraphicCommandsProcessing(3)Attempttopasstherenderingjobtotheclient,leveragingitshardwareaccelerationabilitiesRenderingonthehostsidebysoftwareorGPUisdoneasalastresortReleaseacommandonlywhenCompletelycoveredbyothercommandsandtherearenodependenciesonitRunningoutofresources,thecommandisrenderedtotheframebufferWhentheguestneedstoreadfromtheframebufferCommandrenderedtoframebuffer&deletedfromtreeSpiceClientGuestQEMU/KVMSpiceServer(libspice)SpiceClientClientDevicesHostSpiceAgentDriversGuestQEMU/KVMSpiceServer(libspice)SpiceClientClientHostSpiceClientEnd-userinterfaceCross-platformLinux&WindowsGenericclasses&interfacesParallelimplementationofplatform-specificareasDoesnotrequireanycodecsSPICEFRIENDS&FAMILYQXLDevice&DriverGuestQEMU/KVMSpiceServer(libspice)SpiceClientClientQXLDevice(s)HostGraphicEngineQXLDriversQXLDevice&DriverTransparentremotedisplaySpecificQEMUPCIdisplaydeviceParavirtualdeviceforenhancedperformanceTransfergenericgraphiccommandstoserverPixmaphashing&cachehintCursorsupportWindowsdriver&betaX11driveralreadyimplementedSupportstandardVGAmodeaswellNodriversrequiredBootstagedisplayVDIPortDevice&DriverGuestQEMU/KVMSpiceServer(libspice)SpiceClientClientVDIPortDeviceHostSpiceAgentVDIPortDriverVDIPortDeviceVDIport-QEMUPCIdeviceusedforcommunicationwithguestagentAgentcommunicateswithbothclient&serverusingagent-dedicatedprotocolWindowsguestdriveralreadyimplementedOptionalcomponentEnhancesuserexperiencePerformsguest-orientedtasksInjectsmousepositionandstateDisplaysettingsconfigurationSpiceAgentSPICEOPTIMIZATIONSImageCachingClientimagecaching:pixmaps,palettesandcursorsEliminatessendingredundantinstancesofanimageImagearrivesfromdriverwithuniqueid&cachehintPixmapcacheissharedamongallthedisplaysSynchronizedbetweentheserverandclientServermanagescacheImageCompressionLossless-commandsdependency,preventsartifactsImage-basedQuic-basedonSFALICLZ-LZSSadjustedtoimagesGlobalLZ(GLZ)LZwithahistory-basedglobaldictionaryTakesadvantageofrepeatingpatternsamongimagesAuto-HeuristiccompressionchoiceperimageSyntheticimages-LZ/GLZPhotos-QuicVideoCompressionServerheuristicallyidentifiesvideostreamsUsingthecommandstreeAreasconstantlyupdatedforaperiodoftimeSendthemasvideostreamcodedusingM-JPEGSavesalotoftraffic,improvingSpiceperformance,especiallyinWANReducesclient&serverCPUconsumptionDoesnotrequireanycodecsHardwareAccelerationBasicclientrendering-usingCairoCross-platform,device-independent2DlibraryClientHWaccelerationGDIinWindowsOpenGLinLinux(experimental)RenderingbytheclientGPUinsteadofCPUHighperformancerenderingBetterclientCPUutilizationServerHWaccelerationusesOpenGLSharingcodewiththeLinuxclientMousemodesClientmodeClientmouseusedastheeffectivepointingdeviceGuestagentusedforcursorpositioninjectionCursorshape&visibility-updatedinadedicatedchannelSmoothcursormotionandresponsivenessAppropriateforWANServermodeServercontrolsmousepositionAlwayssynchronizedOtherFeaturesMultipleMonitors-testedon4,noreallimitAutomaticconfigurationofguestdisplays2-wayAudioandLip-syncAudioplaybackandrecordingPlaybackcompressedusingCELTLip-sy