1.5. Red Hat GFS

Red Hat GFS 是​​​​​​​允​​​​​​​许​​​​​​​群​​​​​​​集​​​​​​​节​​​​​​​点​​​​​​​同​​​​​​​时​​​​​​​访​​​​​​​问​​​​​​​某​​​​​​​个​​​​​​​共​​​​​​​享​​​​​​​的​​​​​​​块​​​​​​​设​​​​​​​备​​​​​​​的​​​​​​​群​​​​​​​集​​​​​​​文​​​​​​​件​​​​​​​系​​​​​​​统​​​​​​​。​​​​​​​GFS 是​​​​​​​一​​​​​​​个​​​​​​​原​​​​​​​生​​​​​​​的​​​​​​​(native)文​​​​​​​件​​​​​​​系​​​​​​​统​​​​​​​,它​​​​​​​直​​​​​​​接​​​​​​​和​​​​​​​ Linux 内​​​​​​​核​​​​​​​文​​​​​​​件​​​​​​​系​​​​​​​统​​​​​​​接​​​​​​​口​​​​​​​的​​​​​​​ VFS 层​​​​​​​进​​​​​​​行​​​​​​​通​​​​​​​信​​​​​​​。​​​​​​​GFS 使​​​​​​​用​​​​​​​分​​​​​​​布​​​​​​​式​​​​​​​元​​​​​​​数​​​​​​​据​​​​​​​和​​​​​​​多​​​​​​​个​​​​​​​日​​​​​​​志​​​​​​​来​​​​​​​优​​​​​​​化​​​​​​​群​​​​​​​集​​​​​​​操​​​​​​​作​​​​​​​。​​​​​​​要​​​​​​​维​​​​​​​护​​​​​​​文​​​​​​​件​​​​​​​系​​​​​​​统​​​​​​​的​​​​​​​完​​​​​​​整​​​​​​​性​​​​​​​,GFS 使​​​​​​​用​​​​​​​一​​​​​​​个​​​​​​​锁​​​​​​​管​​​​​​​理​​​​​​​器​​​​​​​来​​​​​​​协​​​​​​​调​​​​​​​ I/O。​​​​​​​当​​​​​​​节​​​​​​​点​​​​​​​修​​​​​​​改​​​​​​​了​​​​​​​ GFS 文​​​​​​​件​​​​​​​系​​​​​​​统​​​​​​​上​​​​​​​的​​​​​​​数​​​​​​​据​​​​​​​,这​​​​​​​个​​​​​​​改​​​​​​​动​​​​​​​马​​​​​​​上​​​​​​​为​​​​​​​使​​​​​​​用​​​​​​​这​​​​​​​个​​​​​​​文​​​​​​​件​​​​​​​系​​​​​​​统​​​​​​​的​​​​​​​其​​​​​​​他​​​​​​​群​​​​​​​集​​​​​​​节​​​​​​​点​​​​​​​可​​​​​​​见​​​​​​​。​​​​​​​
使​​​​​​​用​​​​​​​ Red Hat GFS,您​​​​​​​可​​​​​​​以​​​​​​​从​​​​​​​如​​​​​​​下​​​​​​​几​​​​​​​方​​​​​​​面​​​​​​​受​​​​​​​益​​​​​​​并​​​​​​​实​​​​​​​现​​​​​​​应​​​​​​​用​​​​​​​程​​​​​​​序​​​​​​​的​​​​​​​最​​​​​​​大​​​​​​​正​​​​​​​常​​​​​​​运​​​​​​​行​​​​​​​时​​​​​​​间​​​​​​​:
  • 简​​​​​​​化​​​​​​​数​​​​​​​据​​​​​​​基​​​​​​​础​​​​​​​结​​​​​​​构​​​​​​​
    • 整​​​​​​​个​​​​​​​群​​​​​​​集​​​​​​​只​​​​​​​需​​​​​​​安​​​​​​​装​​​​​​​一​​​​​​​次​​​​​​​应​​​​​​​用​​​​​​​程​​​​​​​序​​​​​​​或​​​​​​​补​​​​​​​丁​​​​​​​
    • 消​​​​​​​除​​​​​​​对​​​​​​​应​​​​​​​用​​​​​​​程​​​​​​​序​​​​​​​数​​​​​​​据​​​​​​​的​​​​​​​冗​​​​​​​余​​​​​​​拷​​​​​​​贝​​​​​​​(复​​​​​​​制​​​​​​​)的​​​​​​​需​​​​​​​要​​​​​​​。​​​​​​​
    • 启​​​​​​​用​​​​​​​多​​​​​​​个​​​​​​​客​​​​​​​户​​​​​​​对​​​​​​​数​​​​​​​据​​​​​​​的​​​​​​​并​​​​​​​行​​​​​​​读​​​​​​​/写​​​​​​​操​​​​​​​作​​​​​​​。​​​​​​​
    • 简​​​​​​​化​​​​​​​备​​​​​​​份​​​​​​​和​​​​​​​恢​​​​​​​复​​​​​​​(只​​​​​​​需​​​​​​​要​​​​​​​备​​​​​​​份​​​​​​​或​​​​​​​恢​​​​​​​复​​​​​​​一​​​​​​​个​​​​​​​文​​​​​​​件​​​​​​​系​​​​​​​统​​​​​​​)。​​​​​​​
  • 最​​​​​​​大​​​​​​​化​​​​​​​对​​​​​​​存​​​​​​​储​​​​​​​资​​​​​​​源​​​​​​​的​​​​​​​使​​​​​​​用​​​​​​​;最​​​​​​​小​​​​​​​化​​​​​​​存​​​​​​​储​​​​​​​的​​​​​​​管​​​​​​​理​​​​​​​开​​​​​​​销​​​​​​​。​​​​​​​
    • 将​​​​​​​存​​​​​​​储​​​​​​​作​​​​​​​为​​​​​​​一​​​​​​​个​​​​​​​整​​​​​​​体​​​​​​​而​​​​​​​不​​​​​​​是​​​​​​​根​​​​​​​据​​​​​​​分​​​​​​​区​​​​​​​管​​​​​​​理​​​​​​​。​​​​​​​
    • 通​​​​​​​过​​​​​​​消​​​​​​​除​​​​​​​数​​​​​​​据​​​​​​​复​​​​​​​制​​​​​​​的​​​​​​​需​​​​​​​要​​​​​​​从​​​​​​​而​​​​​​​减​​​​​​​少​​​​​​​总​​​​​​​体​​​​​​​的​​​​​​​存​​​​​​​储​​​​​​​需​​​​​​​求​​​​​​​。​​​​​​​
  • 通​​​​​​​过​​​​​​​即​​​​​​​时​​​​​​​添​​​​​​​加​​​​​​​服​​​​​​​务​​​​​​​器​​​​​​​或​​​​​​​存​​​​​​​储​​​​​​​空​​​​​​​间​​​​​​​来​​​​​​​无​​​​​​​缝​​​​​​​地​​​​​​​扩​​​​​​​展​​​​​​​群​​​​​​​集​​​​​​​。​​​​​​​
    • 不​​​​​​​需​​​​​​​要​​​​​​​复​​​​​​​杂​​​​​​​的​​​​​​​技​​​​​​​术​​​​​​​来​​​​​​​对​​​​​​​存​​​​​​​储​​​​​​​空​​​​​​​间​​​​​​​分​​​​​​​区​​​​​​​。​​​​​​​
    • 通​​​​​​​过​​​​​​​挂​​​​​​​载​​​​​​​至​​​​​​​普​​​​​​​通​​​​​​​文​​​​​​​件​​​​​​​系​​​​​​​统​​​​​​​来​​​​​​​实​​​​​​​时​​​​​​​在​​​​​​​群​​​​​​​集​​​​​​​里​​​​​​​添​​​​​​​加​​​​​​​服​​​​​​​务​​​​​​​器​​​​​​​。​​​​​​​
运​​​​​​​行​​​​​​​ Red Hat GFS 的​​​​​​​节​​​​​​​点​​​​​​​都​​​​​​​用​​​​​​​ Red Hat Cluster Suite 配​​​​​​​置​​​​​​​和​​​​​​​管​​​​​​​理​​​​​​​工​​​​​​​具​​​​​​​进​​​​​​​行​​​​​​​配​​​​​​​置​​​​​​​和​​​​​​​管​​​​​​​理​​​​​​​。​​​​​​​卷​​​​​​​管​​​​​​​理​​​​​​​通​​​​​​​过​​​​​​​群​​​​​​​集​​​​​​​逻​​​​​​​辑​​​​​​​卷​​​​​​​管​​​​​​​理​​​​​​​器​​​​​​​(Cluster Logical Volume Manager,CLVM)进​​​​​​​行​​​​​​​管​​​​​​​理​​​​​​​。​​​​​​​Red Hat GFS 在​​​​​​​ Red Hat 群​​​​​​​集​​​​​​​的​​​​​​​ GFS 节​​​​​​​点​​​​​​​间​​​​​​​提​​​​​​​供​​​​​​​数​​​​​​​据​​​​​​​共​​​​​​​享​​​​​​​。​​​​​​​GFS 提​​​​​​​供​​​​​​​ Red Hat 群​​​​​​​集​​​​​​​的​​​​​​​ GFS 节​​​​​​​点​​​​​​​的​​​​​​​单​​​​​​​一​​​​​​​的​​​​​​​、​​​​​​​一​​​​​​​致​​​​​​​的​​​​​​​文​​​​​​​件​​​​​​​系​​​​​​​统​​​​​​​命​​​​​​​名​​​​​​​空​​​​​​​间​​​​​​​的​​​​​​​视​​​​​​​图​​​​​​​。​​​​​​​GFS 允​​​​​​​许​​​​​​​安​​​​​​​装​​​​​​​和​​​​​​​运​​​​​​​行​​​​​​​应​​​​​​​用​​​​​​​程​​​​​​​序​​​​​​​而​​​​​​​无​​​​​​​需​​​​​​​了​​​​​​​解​​​​​​​底​​​​​​​层​​​​​​​的​​​​​​​存​​​​​​​储​​​​​​​基​​​​​​​础​​​​​​​结​​​​​​​构​​​​​​​。​​​​​​​而​​​​​​​且​​​​​​​,GFS 提​​​​​​​供​​​​​​​通​​​​​​​常​​​​​​​在​​​​​​​企​​​​​​​业​​​​​​​环​​​​​​​境​​​​​​​才​​​​​​​要​​​​​​​求​​​​​​​的​​​​​​​功​​​​​​​能​​​​​​​,如​​​​​​​配​​​​​​​额​​​​​​​(quota)、​​​​​​​多​​​​​​​重​​​​​​​日​​​​​​​志​​​​​​​和​​​​​​​多​​​​​​​路​​​​​​​径​​​​​​​(multipath)支​​​​​​​持​​​​​​​。​​​​​​​
GFS 根​​​​​​​据​​​​​​​存​​​​​​​储​​​​​​​环​​​​​​​境​​​​​​​的​​​​​​​性​​​​​​​能​​​​​​​、​​​​​​​可​​​​​​​伸​​​​​​​缩​​​​​​​性​​​​​​​和​​​​​​​经​​​​​​​济​​​​​​​性​​​​​​​需​​​​​​​要​​​​​​​来​​​​​​​提​​​​​​​供​​​​​​​网​​​​​​​络​​​​​​​存​​​​​​​储​​​​​​​的​​​​​​​通​​​​​​​用​​​​​​​方​​​​​​​法​​​​​​​。​​​​​​​本​​​​​​​章​​​​​​​提​​​​​​​供​​​​​​​一​​​​​​​些​​​​​​​非​​​​​​​常​​​​​​​基​​​​​​​础​​​​​​​的​​​​​​​、​​​​​​​简​​​​​​​略​​​​​​​的​​​​​​​信​​​​​​​息​​​​​​​来​​​​​​​帮​​​​​​​助​​​​​​​您​​​​​​​理​​​​​​​解​​​​​​​ GFS。​​​​​​​
You can deploy GFS in a variety of configurations to suit your needs for performance, scalability, and economy. For superior performance and scalability, you can deploy GFS in a cluster that is connected directly to a SAN. For more economical needs, you can deploy GFS in a cluster that is connected to a LAN with servers that use GNBD (Global Network Block Device) or to iSCSI (Internet Small Computer System Interface) devices. (For more information about GNBD, refer to 第 1.7 节 “全​​​​​​​球​​​​​​​网​​​​​​​络​​​​​​​块​​​​​​​设​​​​​​​备​​​​​​​”.)
下​​​​​​​面​​​​​​​的​​​​​​​章​​​​​​​节​​​​​​​提​​​​​​​供​​​​​​​的​​​​​​​例​​​​​​​子​​​​​​​,展​​​​​​​示​​​​​​​了​​​​​​​怎​​​​​​​样​​​​​​​部​​​​​​​署​​​​​​​ GFS 来​​​​​​​满​​​​​​​足​​​​​​​您​​​​​​​对​​​​​​​性​​​​​​​能​​​​​​​、​​​​​​​灵​​​​​​​活​​​​​​​性​​​​​​​和​​​​​​​经​​​​​​​济​​​​​​​性​​​​​​​的​​​​​​​需​​​​​​​要​​​​​​​:

注意

GFS 部​​​​​​​署​​​​​​​示​​​​​​​例​​​​​​​只​​​​​​​是​​​​​​​演​​​​​​​示​​​​​​​了​​​​​​​基​​​​​​​本​​​​​​​的​​​​​​​配​​​​​​​置​​​​​​​;在​​​​​​​实​​​​​​​践​​​​​​​中​​​​​​​,您​​​​​​​可​​​​​​​能​​​​​​​需​​​​​​​要​​​​​​​将​​​​​​​这​​​​​​​些​​​​​​​配​​​​​​​置​​​​​​​进​​​​​​​行​​​​​​​组​​​​​​​合​​​​​​​。​​​​​​​

1.5.1. 出​​​​​​​众​​​​​​​的​​​​​​​性​​​​​​​能​​​​​​​和​​​​​​​灵​​​​​​​活​​​​​​​性​​​​​​​

You can obtain the highest shared-file performance when applications access storage directly. The GFS SAN configuration in 图 1.11 “GFS with a SAN” provides superior file performance for shared files and file systems. Linux applications run directly on cluster nodes using GFS. Without file protocols or storage servers to slow data access, performance is similar to individual Linux servers with directly connected storage; yet, each GFS application node has equal access to all data files. GFS supports over 300 GFS nodes.
GFS with a SAN

图 1.11. GFS with a SAN