嵌入式系统版本2.6.39,nandflash上根文件系统是jffs2,sd卡用来存数据文件系统是ext3,正常运行一段时间后,突然发现iowait 99%,应用全部被挂起。 登入系统查看:是卡在写SD数据上,此时在SD卡还能vi新建文件。帮忙分析看看是什么原因导致的,谢谢 echo 1 > /proc/sys/vm/block_dump dmesg |awk -F " " '{print $2}'|sort|uniq -c|sort -rn|head -n 100 259 on 259 inode 259 dirtied 254 p 254 mmcb...
by tomsen2013 - Linux系统管理 - 2014-05-21 08:34:38 阅读(765) 回复(2)
when I use "top" to check my system. I find iowait 80%,my memory is all free and CPU is all free. my system is very slow. how I will do ,or find the problem? thanks
when I use \"top\" to check my system.\r\nI find iowait 80%,my memory is all free and CPU is all free.\r\nmy system is very slow.\r\n\r\nhow I will do ,or find the problem?\r\n\r\n\r\nthanks
雖然跑linux 無法做到real-time 我想知道假如我有3個應用程式同時執行且不會停止, linux 如何分配process1/2/3 執行時間? process1 -> context switch -> process2 -> context switch -> process3 -> context switch -> process1
As its name implies, the state field of the process descriptor describes what is currently happening to the process. It consists of an array of flags, each of which describes a possible process state. In the current linux version, these states are mutually exclusive, and hence exactly one flag of state always is set; the remaining flags are cleared. The following are the possible process states: ...
Take a guided tour from the Master Boot Record to the first user-space application Level: Introductory M. Tim Jones ( [email=mtj@mtjones.com?subject=Inside the linux boot process&cc=tomyoung@us.ibm.com]mtj@mtjones.com[/email] ), Consultant Engineer, Emulex 31 May 2006 The process of booting a linux® system consists of a number of stages. But whether you're booting a standard x86 desktop or a...
Inside the linux boot process Take a guided tour from the Master Boot Record to the first user-space application Document options Print this page E-mail this page Document options requiring JavaScript are not displayed New site feature dW radio -- Listen to our podcasts Rate this page Help us improve this content Level: Introductory M. Tim Jones ( [email=mtj@mtjones.com?subject...
这一节主要介绍了,内核创建一个子进程的过程。介绍了创建一个进程需要的十八个步骤。 Creating processes Unix operating systems rely heavily on process creation to statify user requests.As an example,the shell process creats a new process that executes another copy of the shell whenever the user enters a command. Traditional unix systems treat all processes in the same way:resources owned by the par...
这一节,主要描述了进程切换的过程。讲的十分清楚:) process Swithing In order to control the execution of processes,the kernel must be able to suspendthe execution of the process running on the cpu and resume the execution of some other process previously suspended.this activity is called process switching ,task switching,or context switching.the following sections describe the element of process...
这一节,主要介绍了进程描述符的数据结构,其中重要介绍了,进程状态,task数组以及相应的操作,进程链表,和pidhash table and chained lists,The list of task free entries,Parenthood Relationships Among process 和Wait Queues。 Charpter 3 process A process is usually defined as an instance of a program in execution. process Descriptor in order to manage process ,the kernel must have a clear picture of w...
1.redhat 4.5uname -r 2.6.9-55.ELsmp 2.[root@~]# iostat -x 2 linux 2.6.9-55.ELsmp 10/26/2009 avg-cpu: %user %nice %sys %iowait %idle 4.67 0.00 1.83 13.15 80.35 Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 14.89 8.35 204.64 2.82 506.87 89.38 253.43 44.69 2.87 0.47 ...