操作系统原理与设计第4章Threads2（线程2）陈香兰中国科学技术大学计算机学院December20,2009......提纲OSExamplesforThreadThreadSchedulingOSExamplesforThreadScheduling小结和作业......OutlineOSExamplesforThreadThreadSchedulingOSExamplesforThreadScheduling小结和作业......WindowsXPThreadsIIAnWindowsXPapplicationrunsasaseperateprocess,andeachprocessmaycontainoneormorethreads.IImplementstheone-to-onemappingIeachuser-levelthreadmapstoanassotiatedkernelthreadIanythreadbelongingtoaprocesscanaccesstheaddressspaceoftheprocessIEachthreadcontainsIAthreadidIRegistersetISeparateuserandkernelstacksIPrivatedatastorageareaITheregisterset,stacks,andprivatestorageareaareknownasthecontextofthethreads......WindowsXPThreadsIIITheprimarydatastructuresofathreadinclude:IETHREAD(executivethreadblock)IKTHREAD(kernelthreadblock)ITEB(threadenvironmentblock)......WindowsXPThreadsIII......LinuxThreadsILinuxreferstothemastasksratherthanthreadsIThreadcreationisdonethroughclone()systemcallIclone()allowsachildtasktosharetheaddressspaceoftheparenttask(process)Iclone()VS.fork()......JavaThreadsIJava在语言级提供线程创建和管理支持功能IJavathreadsaremanagedbytheJVM,notuser-levellibraryorkernelIJavathreadsmaybecreatedby:IExtendingThreadclassIImplementingtheRunnableinterfaceJava......ThreadStates......OutlineOSExamplesforThreadThreadSchedulingOSExamplesforThreadScheduling小结和作业......ThreadSchedulingIuser-levelthread:kernel-levelthread(orLWP)ILocalScheduling–HowthethreadslibrarydecideswhichthreadtoputontoanavailableLWPImany-to-one,many-to-manymodelsIprocess-contentionscope,PCSIGlobalScheduling–HowthekerneldecideswhichkernelthreadtorunnextImany-to-one,many-to-many&one-to-onemodelsIsystem-contentionscope,SCS......PthreadSchedulingAPIIIPOSIXPthreadAPIallowsspecifyingeitherPCSorSCSduringthreadcreationIPTHREADSCOPEPROCESS,many-to-manyIPTHREADSCOPESYSTEM,one-to-oneIcreateandbindanLWPforeachuser-levelthreadIexample#include<pthread.h>#includ