KVM Architecture Overview.pdf

KVM Architecture Oerie! 2015 Edition

Stefan Hajnoczi >

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ertain oerations tra o"t to the hyer!isor VM-7 VM+ES:ME

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9"est memory address

Ho! *+M u&e& (-.(o 3EM: "sersace rocess "ses !m.o dri!er to e%ec"te )"est code/

open("/dev/kvm") ioctl(KVM_CREATE_VM) ioctl(KVM_CREATE_VCPU) for (;;)  ioctl(KVM_RU!) #itc$ (e%it_re&on)  c&e KVM_E'T_* /+ ,,, +/ c&e KVM_E'T_-.T* /+ ,,, +/  

*+M /roce&& -o#e% 3EM: is a "sersace rocess 9"est +*M

:nri!i#e)ed and iso#ated "sin) SE$in"% for sec"rity

3EM:

Each KVM !;: is a thread

Host erne#

Host erne# sched"#er decides hen !;:s r"n

3inu4 conce/t& a//%y to *+MKVM Since 3EM: is a "sersace rocess( the "s"a# $in"% too#s or/ sB1C( toB1C( etc see 3EM: rocesses and threads tcd"mB&C sees ta netor traffic ,#traceB&C sees dis ?- re"ests Systema and erf see 3EM: acti!ity etc

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a##,acs or coro"tines

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V;: threads e%ec"te in ara##e# Secific tass that o"#d ,#oc e!ent #oo are done in threads( e.). remote dis#ay encodin)( +*M #i!e mi)ration or( !irtio=,# data#ane( etc +est of 3EM: code r"ns "nder )#o,a# m"te%

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;ara!irt"a#ized de!ices for ,etter erformance

Most de!ices are em"#ated and not rea# ●

?so#ation from host for sec"rity

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Sharin) of reso"rces ,eteen )"ests

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Architecture irtio #eice& KVM im#ements !irtio de!ice mode#s ●

net( ,#( scsi( seria#( rn)( ,a##oon

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See htt/docs.oasis=oen.or)!irtio for secs

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Architectura% e4ce/tion ho&t in7(erne% #eice& Most de!ice em"#ation is ,est done in "sersace ●

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!host dri!ers em"#ate !irtio de!ices in host erne# ●

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KVM Architecture Overview.pdf

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