AIX 5L 性能优化,第 1 部分 监视 CPU

AIX 5L 内存性能优化之使用ps、sar、svmon 和vmstat 监视内存的使用AIX 5L 内存性能优化之使用ps、sar、svmon 和vmstat 监视内存的使用,通过命令监控AIX系统的内存使用状况,进而进行系统内存的性能优化,是一个系统管理员对系统优化要做的基本工作!内存子系统中最重要的优化部分并不涉及到实际的优化工作。

在对您的系统进行优化之前，必须弄清楚主机系统的实际运行情况。

要做到这一点，AIX® 管理员必须知道应该使用何种工具，以及如何对他或她将要捕获的数据进行分析。

再次说明近期发表的一些其他优化文章中所介绍的内容，您在对系统进行正确地优化之前，必须首先监视主机，无论它是在逻辑分区(LPAR) 运行还是在自己的物理服务器上运行。

您可以使用许多命令来捕获和分析数据，所以您需要了解这些命令，以及其中的哪个命令最适合于将要进行的工作。

在捕获了相关的数据之后，您需要对结果进行分析。

有些问题乍看起来像是一个中央处理单元(CPU) 的问题，而经过分析之后，可以正确地诊断为内存或I/O 问题，前提是您使用了合适的工具捕获数据，并且知道如何进行分析工作。

仅当正确地完成了这些工作之后，您才可以考虑对系统进行实际的更改。

如果医生不了解您的病史和目前的症状，就无法诊治疾病，同样地，您也需要在优化子系统之前对其进行诊断。

如果在出现CPU 或者I/O 瓶颈的情况下，对内存子系统进行优化，这将是毫无帮助的，甚至可能会影响主机的正常运行。

本文将帮助您了解正确地实施诊断工作的重要性。

您将看到，性能优化并不仅仅只是进行实际的优化工作。

在您将要学习的工具中，有一些是通用的监视工具，所有版本的UNIX 都提供了这些工具，另外还有一些工具是专门为AIX 编写的。

有些工具为AIX Version 5.3 进行了优化，同时还专门为AIX 5.3 系统开发了一些新的工具。

生成基准数据是非常重要的，这一点无论重申多少次都不为过。

AIX 5L 内存性能优化内容提要:AIX 5L 内存性能优化说明:什么是交换（分页）空间？它是与VMM 有关的。

VMM 使用交换（分页）空间存储没有使用活动RAM 的进程。

正是因为这个目的，交换空间是系统整体性能的关键组件。

作为一名管理员，您需要了解如何监视和优化您的分页参数。

分页空间本身是一个特殊的逻辑卷，它存储了当前不访问的信息。

您必须确保您的系统拥有足够的分页空间。

如果分页空间过小，整个进程可能会丢失，并且当所有的空间都占满后，系统可能会崩溃。

尽管值得再次说明，分页空间是VMM 中的一部分，但是更重要的是真正地理解内核如何将进程调入到RAM 中，过多的分页肯定会对性能造成影响。

AIX 通过将内核与VMM 紧密集成在一起，实现了一种称为请求分页的方法。

事实上，内核本身的大部分都驻留在虚拟内存中，这样可以帮助释放它的片段空间以用于其他进程。

>> 请求分页大多数管理员都认为分页是一件很麻烦的事情。

实际上，分页是AIX 所完成的任务中非常必要的一部分，这是由于AIX 内核与VMM 及其请求分页的实现进行了紧密的集成。

请求分页的工作原理是，内核一次仅加载部分页面到实际内存中。

当CPU 需要另一个页面时，它会到RAM 中查找。

如果无法在RAM 中找到这个页面，则出现一次缺页，然后向内核发出信号以便从磁盘中加载更多的页面到RAM。

请求分页的一个优点是，分页空间不需要非常大，因为数据总是在分页空间和RAM 之间不断地交换。

在较早的UNIX? 系统中，将分页预先分配到磁盘，无论使用还是不使用它们。

这使得所分配的磁盘空间可能永远不会被使用。

从本质上说，请求分页可以避免盲目地分配磁盘空间。

应该使得进程的交换最少，因为许多任务可能存储在RAM 中。

的确如此，因为进程（页面）只有一部分存储在RAM 中。

交换指的是什么呢？尽管分页和交换通常可以互换使用，但它们之间存在细微的区别。

如前所述，在进行分页时，进程的部分内容将在磁盘和RAM 之间来回移动。

AIX查看命令1.查看cpu：1.1 #pmcycles (从aix 5.1开始在bos.pmapi.pmsvcs包中)1.2 #lsattr -El proc*2.查看内存：2.1 #lsattr -El mem*2.2 #lsattr -El sys0 -a realmem2.3 #bootinfo -r2.4 #getconf REAL_MEMORY (5L,hpux也有该命令，不过用法有差别。

另外，在aix中还可以用getconf HARDWARE_BITMODE和KERNEL_BITMODE来分别查看机器的硬件和操作系统是32位还是64位)3.查看model，sn：＃uname -Mu 结果如下IBM,7043-150 IBM,01105DE2CE其中IBM,7043-150是model，01105DE2CE中的105DE2CE就是机器上标明的sn:10－5DE2CE，也就是序列号4.查看系统的maitenance level：4.1 #oslevel -r4.2 #instfix -i |grep ML5.查看哪些文件集没有打到相应的maitenance level:#instfix -icqk 5100-02_AIX_ML |grep ":-:" 或#oslevel -rl 5100-026.查看当前运行的fileset的maintenance level:#lslpp -lnotes:PTF用installp安装，APAR用instfix安装7.installp命令7.1 安装在 软件包中的所有的filesets到/usr/sys/inst.images:#installp avX d /usr/sys/inst.images 7.2 清除一个中断的安装和删除所有没有完成的安装#installp C7.3 提交安装（commit）：#installp cgx 或smitty install_commit7.4 删除所有未committed的在./reject.list中的updates，同时将系统带回到以前的maintenance level：#installp rBfx ./reject.list 或smitty install_reject7.5 删除一个安装的软件：#installp ugp V2 .ipsec.rte 或smitty install_remove7.6 列示介质上的所有软件：#installp L d /dev/cd0在超级用户下键入smitty mksysb然后出现对话窗口键入备份装置( 如/dev/rmt0 )，按回车。

优化AIX 7磁盘性能第一部分磁盘I/O概述和长期监控工具【sar+nmon+ topas】简介磁盘 I/O 优化的关键部分涉及到在构建系统之前实现最佳实践。

因为当系统已经启动并处于运行状态时，很难再对数据进行移动，所以需要在规划磁盘和 I/O 子系统环境时正确地完成这项任务，这一点是非常重要的。

这包括物理架构、逻辑磁盘排列以及逻辑卷和文件系统配置。

当系统管理员听到可能出现了磁盘争用问题时，他或她首先会求助于 iostat。

iostat 等同于使用 vmstat 提供有关内存的报告，它是获得有关 I/O 子系统的当前运行概况的一种快速而原始的方法。

尽管运行 iostat 并不是一种完全不合理的反应，但是很早就应该着手考虑磁盘 I/O 的问题，而不是等到必须进行调优的时候。

如果没有从一开始就正确地为环境配置磁盘，那么任何调优工作都无法提供帮助。

而且，有一点非常重要，需要了解磁盘 I/O 的具体情况，以及它与 AIX® 和 your System p™ 硬件之间的关系。

对于磁盘 I/O 调优来说，AIX 特有的工具和实用工具比通用的 UNIX® 命令和工具能够提供更多的帮助，因为它们的任务就是帮助优化本机 AIX 磁盘 I/O 子系统。

在本文中，我们要定义和介绍 AIX I/O 栈，并将其与磁盘性能的物理和逻辑方面关联起来。

本文介绍直接、并发和异步 I/O：它们是什么，如何启用它们，以及如何监控和优化它们。

本文还介绍一些长期监控工具，应该使用它们来帮助优化系统。

听到 iostat 并不是我们推荐的帮助长期收集统计数据的工具，您可能会感到奇怪。

本文讨论 AIX 7 的 beta 版中的支持和变化，包括不同子系统的配置方式方面的变化。

AIX 7 中的主要变化进一步简化了许多 I/O 子系统的操作和配置，这个改进过程从 AIX 6 就开始了。

其结果是许多 I/O 子系统不再需要启用和配置了。

AIX操作系统性能分析报告1）CPU$ vmstat 5 5System configuration: lcpu=8 mem=7744MBkthr memory page faults cpu----- ----------- ------------------------ ------------ ----------- r b avm fre re pi po fr sr cy in sy cs us sy id wa1 5 1943309 1817 0 341 109 2018 6836 0 1246 3524 5000 34 3 32 311 8 1943312 861 0 23 812 1975 2909 0 1227 776 4348 13 3 45 392 6 1945483 1855 0 78 737 1189 1880 0 639 1287 2119 30 1 39 302 5 1949024 1921 0 307 73 1002 2973 0 511 3190 1719 57 1 20 224 9 1959284 2146 0 400 35 2745 21198 0 824 21885 30 45 62 2 12 24从上面结果看出，CPU的idle在12－45之间，wait在22－39之间，表示目前处于空闲状态的CPU基本属于正常；但是处于等待状态的CPU较多，即有较多的进程在等待获取资源后才能进入CPU运行。

2）内存$ vmstat 5 5System configuration: lcpu=8 mem=7744MBkthr memory page faults cpu----- ----------- ------------------------ ------------ ----------- r b avm fre re pi po fr sr cy in sy cs us sy id wa1 5 1943309 1817 0 341 109 2018 6836 0 1246 3524 5000 34 3 32 311 8 1943312 861 0 23 812 1975 2909 0 1227 776 4348 13 3 45 392 6 1945483 1855 0 78 737 1189 1880 0 639 1287 2119 30 1 39 302 5 1949024 1921 0 307 73 1002 2973 0 511 3190 1719 57 1 20 224 9 1959284 2146 0 400 35 2745 21198 0 824 21885 30 45 62 2 12 24从上面看出，avm(激活虚拟内存页)为1.95M*4K=7.8G；fre(物理内存中的空闲页)为1.9k*4k=7.6M,而物理内存有8G,表示物理内存已经被充分利用。

AIX性能调优系统资源（物理资源，逻辑资源）系统瓶颈性能概念一个程序执行步骤性能调整流程Instructor GuideFigure 1-6. Program Execution Hierarchy AU187.0 Notes:IntroductionIn the graphic above, the left side represents hardware entities that are loosely matched to the appropriate operating system entity on the right side. A program must go from the lowest level of being stored on disk, to the highest level being the processor running program instructions.Hardware hierarchy overviewWhen a program runs, it makes its way up the hardware and operating systemhierarchies, more or less in parallel. Each level on the hardware side is scarcer and more expensive than the one below it. There is contention for resources amongprograms and time spent in transitional from one level to the next. Usually, the time required to move from one hardware level to another consists primarily of the latency of the lower level, that is, the time from the issuing of a request to the receipt of the first data.1-18 AIX 5L System Administration III© Copyright IBM Corp. 2000, 2006Course materials may not be reproduced in whole or in partInstructor Guide Disks are the slowest hardware operationBy far the slowest operation that a running program does (other than waiting on a human keystroke) is to obtain code or data from a disk. Disk operations are necessary for read or write requests for programs. System tuning activities frequently turn out to be hunts for unnecessary disk I/O or searching for disk bottlenecks since disk operations are the slowest operations. For example, can the system be tuned to reduce paging? Is one disk too busy causing higher seek times because it has multiple filesystems which have a lot of activity?Real memoryRandom Access Memory (RAM) access is fast compared to disk, but much moreexpensive per byte. Operating systems try to keep program code and data that are in use in RAM. When the operating system begins to run out of free RAM, it needs to make decisions about what types of pages to write out to disk. Virtual memory is the ability of a system to use disk space as an extension of RAM to allow for more efficient use of RAM.Paging and page faultsIf the operating system needs to bring a page into RAM that has been written to disk or has not been brought in yet, a page fault occurs, and the execution of the program is suspended until the page has been read in from disk. Paging is a normal part of the operation of a multi-processing system. Paging becomes a performance issue when free RAM is short and pages which are in memory are paged-out and then paged back in again causing process threads to wait for slower disk operations. How virtual memory works will be covered in another unit of this course.Translation Lookaside Buffers (TLBs)One of the ways that programmers are insulated from the physical limitations of the system is the implementation of virtual memory. The programmer designs and codes the program as though the memory were very large, and the system takes responsibility for translating the program's virtual addresses for instructions and data into realaddresses that are needed to get the instructions and data from RAM. Since thisaddress-translation process is time-consuming, the system keeps the real addresses of recently accessed virtual memory pages in a cache called the Translation Lookaside Buffer (TLB).As long as the running program continues to access a small set of program and data pages, the full virtual-to-real page-address translation does not need to be redone for each RAM access. When the program tries to access a virtual-memory page that does not have a TLB entry, called a TLB miss, dozens of processor cycles, called theTLB-miss latency are required to perform the address translation.© Copyright IBM Corp. 2000, 2006Unit 1. Performance Analysis and Tuning Overview1-19Course materials may not be reproduced in whole or in partInstructor GuideCachesTo minimize the number of times the program has to experience the RAM latency, systems incorporate caches for instructions and data. If the required instruction or data is already in the cache (a cache hit), it is available to the processor on the next cycle (that is, no delay occurs); otherwise, a cache miss occurs. If a given access is both a TLB miss and a cache miss, both delays occur consecutively.Depending on the hardware architecture, there are two or three levels of cache, usually called L1, L2, and L3. If a particular storage reference results in an L1 miss, then L2 is checked. If L2 generates a miss, then the reference goes to the next level, either L3, if it is present, or RAM.Pipeline and registersA pipelined, superscalar architecture allows for the simultaneous processing of multipleinstructions, under certain circumstances. Large sets of general-purpose registers and floating-point registers make it possible to keep considerable amounts of the program's data in registers, rather than continually storing and reloading the data.Operating system hierarchy overviewThe operating system works on a thread level. When a user requests the execution of a program, AIX performs a number of operations to transform the executable program on disk to a running program. First, the directories in the user's current PATH must be scanned to find the correct copy of the program. Then the system loader (not to be confused with ld, the binder) must resolve any external references from the program to shared libraries. Finally, the system branches to the entry point of the program and the resulting page fault causes the program page that contains the entry point to be brought into RAM.Interrupt handlersThe mechanism for notifying the operating system that an external event has taken place is to interrupt the currently running thread and transfer control to an interrupt handler (FLIH or SLIH). Before the interrupt handler can run, enough of thegeneral-purpose registers must be saved to ensure that the system can restore the context of the running thread after interrupt handling is complete.ThreadsA thread is the current execution state of a single instance of a program. In AIX, accessto the processor and other resources is allocated on a thread basis, rather than a process basis. Multiple threads can be created within a process by the application program. Those threads share the resources owned by the process within which they are running.1-20 AIX 5L System Administration III© Copyright IBM Corp. 2000, 2006Course materials may not be reproduced in whole or in partWaiting threadsWhenever an executing thread makes a request that cannot be satisfied immediately, such as an I/O operation (either explicit or as the result of a page fault) or the granting ofa lock, it is put in a Wait state until that request is complete. Normally, this results inanother set of TLB and cache latencies, in addition to the time required for the request itself. However, it also allows other threads which are ready to run to gain access to the CPU.When a thread is replaced by another thread on a CPU, this is a context switch. A context switch can also occur when a thread finishes its timeslice or, as stated above, it must wait for a resource. Whenever a context switch occurs, there may be additional latencies due to cache misses. Context switches are a normal function of amulti-processing system, but an abnormally high rate of context switches could be a symptom of a performance problem.Dispatchable threadsWhen a thread is dispatchable, but not actually running, it is put in a run queue to run on an available CPU. If a CPU is available, it will run right away, otherwise it must wait. Currently dispatched threadThe scheduler chooses the thread that has the strongest claim to use the processor.When the thread is dispatched, the logical state of the processor is restored to what was in effect when the thread was last interrupted.Effect of the use of cache, RAM, and paging space on program performanceAccess time for the various components increase exponentially as you move away from the processor. For example, a one second access time for a 1 GHz CPU would be the equivalent of 100 seconds for a L3 cache access, 6 minutes for a RAM access, and 115 days for a local disk access! As you can see, the closer you are to the core, the faster the access is. Understanding how to reduce more expensive (performance-wise)bottlenecks is key to performance management.© Copyright IBM Corp. 2000, 2006Unit 1. Performance Analysis and Tuning Overview1-21Course materials may not be reproduced in whole or in partFigure 1-8. Performance Analysis Flowchart AU187.0 Notes:Tuning is a processThe flowchart in the visual above can be used for performance analysis and it illustrates that tuning is an iterative process. We will be following this flowchart throughout our course.The starting point for this flowchart is the Normal Operations box. The first piece of data you need is a performance goal. Only by having a goal, or a set of goals, can you tell if there is a performance problem. The goals may be something like a specific response time for an interactive application or a specific length of time in which a batch job needs to complete. Tuning without a specific goal could in fact lead to the degradation of system performance.Once you decide there is a performance problem and you analyze and tune the system, you must then go back to the performance goals to evaluate whether more tuning needs to occur.© Copyright IBM Corp. 2000, 2006Unit 1. Performance Analysis and Tuning Overview1-27Course materials may not be reproduced in whole or in partAdditional testsThe additional tests that you perform at the bottom right of the flowchart relate to the four previous categories of resource contention. If the specific bottleneck is well hidden, or you missed something, then you must keep testing to figure out what is wrong. Even when you think you’ve found a bottleneck, it’s a good idea to do additional tests to identify more detail or to make sure one bottleneck is not masquerading as another. For example, you may find a disk bottleneck, but in reality it’s a memory bottleneck causing excessive paging.1-28 AIX 5L System Administration III© Copyright IBM Corp. 2000, 2006Course materials may not be reproduced in whole or in partFigure 1-9. Performance Analysis Tools AU187.0 Notes:CPU analysis toolsCPU metrics analysis tools include:-vmstat, iostat, sar, lparstat and mpstat which are packaged with bos.acct -ps which is in bos.rte.control-cpupstat which is part of mands-gprof and prof which are in bos.adt.prof-time (built into the various shells) or timex which is part of bos.acct-emstat and alstat are emulation and alignment tools from bos.perf.tools-netpmon, tprof, locktrace, curt, splat, and topas are in bos.perf.tools-trace and trcrpt which are part of bos.sysmgt.trace-truss is in bos.sysmgt.ser_aids1-30 AIX 5L System Administration III© Copyright IBM Corp. 2000, 2006Course materials may not be reproduced in whole or in partInstructor Guide-smtctl is in bos.rte.methods-Performance toolbox tools such as xmperf, 3dmon which are part of perfmgr Memory subsystem analysis toolsSome of the memory metric analysis tools are:-vmstat which is packaged with bos.acct-lsps which is part of bos.rte.lvm-topas, svmon and filemon are part of bos.perf.tools-Performance toolbox tools such as xmperf, 3dmon which are part of perfmgr-trace and trcrpt which are part of bos.sysmgt.trace-lparstat is part of bos.acctI/O subsystem analysis toolsI/O metric analysis tools include:-iostat and vmstat are packaged with bos.acct-lsps, lspv, lsvg, lslv and lvmstat are in bos.rte.lvm-lsattr and lsdev are in bos.rte.methods-topas, filemon, and fileplace are in bos.perf.tools-Performance toolbox tools such as xmperf, 3dmon which are part of perfmgr-trace and trcrpt which are part of bos.sysmgt.traceNetwork subsystem analysis toolsNetwork metric analysis tools include:-lsattr and netstat which are part of .tcp.client-nfsstat and nfs4cl as part of .nfs.client-topas and netpmon are part of bos.perf.tools-ifconfig as part of .tcp.client-iptrace and ipreport are part of .tcp.server-tcpdump which is part of .tcp.server-Performance toolbox tools such as xmperf, 3dmon which are part of perfmgr-trace and trcrpt which are part of bos.sysmgt.trace© Copyright IBM Corp. 2000, 2006Unit 1. Performance Analysis and Tuning Overview1-31Course materials may not be reproduced in whole or in partInstructor GuideAIX 5L V5.3 enhancements to analysis toolsSeveral changes were made in AIX 5L V5.3 to the analysis tools. Changes were made at different maintenance levels for V5.3.The tprof command has new -E option to enable event based profiling and the new -f option allows you to set the sampling frequency for event-based profiling. There were updates to PMAPI including updates to pmlist and there are two new commands for hardware analysis: hpmcount and hpmstat. These are not covered in this course.The topas command has a new -D panel for disk analysis.There are new commands for obtaining statistics specific to a logical partition. These give statistics for POWER Hypervisor activity or for tracking real CPU utilization in a simultaneous multi-threading or shared processor (Micro-Partition) environment. A new register was added called the Processor Utilization Resource Register (PURR) to track logical and virtual processor activity. Commands such as sar and topas willautomatically use the new PURR statistics when in a simultaneous multi-threading or shared processor (Micro-Partition) environment and you will see new columns reporting partition statistics in those environments. Trace-based commands now have new hooks for viewing PURR data. Some commands such as lparstat, mpstat, and smtctl are new for AIX 5L V5.3 and work in a partitioned environment.The AIX 5L Virtualization Performance Management course covers all differences in performance analysis and tuning in a partitioned environment.1-32 AIX 5L System Administration III© Copyright IBM Corp. 2000, 2006Course materials may not be reproduced in whole or in partInstructor GuideFigure 1-10. Performance Tuning Process AU187.0 Notes:OverviewPerformance tuning is one aspect of performance management. The definition ofperformance tuning sounds simple and straight forward, but it’s actually a complex process.Performance tuning involves managing your resources. Resources could be logical (queues, buffers, etc.) or physical (real memory, disks, CPUs, network adapters, etc.).Resource management involves the various tasks listed here. We will examine each of these tasks later.Tuning always must be done based on performance analysis. While there arerecommendations as to where to look for performance problems, what tools to use, and what parameters to change, what works on one system may not work on another. So there is no cookbook approach available for performance tuning that will work for all systems.The wheel graphic in the visual above represents the phases of a more formal tuning project. Experiences with tuning may range from the informal to the very formal where reports and reviews are done prior to changes being made. Even for informal tuning actions, it is essential to plan, gather data, develop a recommendation, implement, and document.Figure 1-11. Performance Tuning Tools AU187.0 Notes:CPU tuning toolsCPU tuning tools include:-nice, renice, and setpri modify priorities.nice and renice are in the bos.rte.control fileset.setpri is a command available with the perfpmr package.-schedo (schedtune in AIX 5L V5.1) modifies scheduler algorithms (in the bos.perf.tune fileset).-bindprocessor binds processes to CPUs (in the bos.mp fileset).-chdev modifies certain system tunables (in the bos.rte.methods fileset).-bindintcpu can bind an adapter interrupt to a specific CPU (in thedevices.chrp.base.rte fileset).-procmon is in bos.perf.gtools.Instructor GuideMemory tuning toolsMemory tuning tools include:-vmo and ioo (vmtune in AIX 5L V5.1) for various VMM, file system, and LVM parameters (in bos.perf.tune fileset)-chps and mkps modify paging space attributes (in bos.rte.lvm fileset)-fdpr rearranges basic blocks in an executable so that memory footprints become smaller and cache misses are reduced (in perfagent.tools fileset) -chdev modifies certain system tunables (in bos.rte.methods fileset)I/O tuning toolsI/O tuning tools include:-vmo and ioo modify certain file system and LVM parameters (in bos.perf.tune fileset) (Use vmtune prior to AIX 5L V5.2.)-chdev modifies system tunables such as disk and disk adapter attributes (in bos.rte.methods fileset)-migratepv moves logical volumes from one disk to another (in bos.rte.lvm fileset) -lvmo displays or sets pbuf tuning parameters (in bos.rte.lvm fileset)-chlv modifies logical volume attributes (in bos.rte.lvm fileset)-reorgvg moves logical volumes around on a disk (in bos.rte.lvm fileset)Network tuning toolsNetwork tuning tools include:-no modifies network options (in .tcp.client fileset)-nfso modifies NFS options (in .nfs.client fileset)-chdev modifies network adapter attributes (in bos.rte.methods fileset)-ifconfig modifies network interface attributes (in .tcp.client fileset)CPU在定位CPU性能问题时，从监视 CPU 使用率的统计数据入手。

基于AIX系统的自动监控的运行性能优化及应用研究摘要 aix是ibm公司pc机型机专用的unix操作系统,本文主要通过不同的分析方法, aix操作系统为主要运行平台,对与aix系统运行性能相关的网络子系统主要方面分别进行了深入探讨,结合分析和优化方法对基于aix系统的自动监控系统进行了具体的性能分析并提出了优化方案,并取得了较好的优化效果,能够保障企业计算机系统运行的高效性能。

关键词 pc机;aix操作系统;自动监控;性能优化中图分类号tp39 文献标识码a 文章编号1674-6708(2010)31-0209-02计算机自动监控系统的运行性能优化及应用是一项综合性的复杂工作,应考虑cpu处理能力,内存的大小、数据冗余与数据存储的能力等多个方面,尽量优化每个部件,才能充分保障计算机自动监控系统运行的高效,可靠和安全。

因此,对系统性能进行分析和优化,对企业的信息化建设有一定的指导作用。

本文为此主要针对pc机网络子系统探讨基于aix系统的自动监控运行性能优化及应用方法。

1 pc机网络子系统自动监控介绍pc机网络子系统自动监控由nfs,nis,samba等几部分组成等。

其中nfs是实现两机间进行通讯访问的一种简单方法,nfs本身的服务并没有提供资料传递的协议,但是它却能进行文件的共享。

原因就是nfs使用到一些其它相关的传输协议,而这些传输的协议就是远程过程调用(rpc)。

nfs也可以视为一个rpc server。

需要说明的是,要挂载nfsserver的client pc主机,也需要同步启动远程过程调用。

这样server端和client端才能根据远程过程调用协议进行数据共享。

网络信息服务nis则是一种集中管理系统通用访问文件的分布式数据库系统,在嵌入式linux实验过程中,我们通过配置nfs实现pc机和实验箱arm-linux平台之间的访问。

原理是在pc 机linux中开启nfs服务,设置一个共享目录(这里是/arm2410),所有的源码编辑改动都可以在pc机中进行方便的修改,在arm-linux 实验环境中,将pc-linux的/arm2410目录远程mount到本地,实现两机间的同步读写访问,这样程序就可以方便的在arm-linux中运行测试。