Re: Process states inside the linux kernel. [Especially about the STATE D]

vamsi krishna wrote:

Hello All,

 I have been debugging a program which takes huge memory around 12Gb
(On a 64-bit machine). I was trying to monitor the VmSize and RSS
sizes using top command for this process. I frequently see that the
process STATUS changes its state from 'D' to 'R' most of the time its
in the state 'D'.

 I looked at the manual it says D  uninterruptable sleep state (I have
googled on this but could'nt find much information about this stage).

As far as my text book knowledge, the process is either 1). Running'R' 2.) Ready 'Re' 3.) Wait (for I/O) W .


 So what is 'uninterruptable sleep state' D ? when does the process is
put in this state?

 Can someone releate me the states cycle of the process in linux kernel.

 Really appreciate your time and effort.

It is called D because originally it stood for Disk, and was used forwhen the process was blocked waiting to be swapped back in from thedisk. These days it is still mostly used for when the process is blockedeither handling a page fault or in a system call that does blocking diskIO.



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

References:
- Process states inside the linux kernel. [Especially about the STATE D]
  - From: "vamsi krishna" <[email protected]>

Prev by Date: [2.6 patch] remove the CONFIG_CC_ALIGN_* options
Next by Date: [2.6 patch] unexport install_page
Previous by thread: Process states inside the linux kernel. [Especially about the STATE D]
Next by thread: [2.6 patch] mm/slab: unexport kmem_cache_alloc_node
Index(es):
- Date
- Thread

[Index of Archives] [Kernel Newbies] [Netfilter] [Bugtraq] [Photo] [Stuff] [Gimp] [Yosemite News] [MIPS Linux] [ARM Linux] [Linux Security] [Linux RAID] [Video 4 Linux] [Linux for the blind] [Linux Resources]