That was a very good piece of information. I really got the OOM now. One small doubt though. It describes that OOM selects the process to kill after some initial checking about the failures in last 5 sec , 10 sec and etc... Then it pick up the fresh process with large VM. Now in this time between selecting the process and killing the process , is every other thing locked? What if the Process that requested the mem got some mem in the mean time.. I guess there will be one more round of checking before actually killing the process. I may be wrong .. but this is what I deduce from the article... Also this will be a very rare phenomenon as the HIGH MEM zone will always give us the enough mem with KSWAPDEMON. Hope I am not wrong here. :) Thanks. -- Abhijit. -----Original Message----- From: kernelnewbies-bounce@xxxxxxxxxxxx [mailto:kernelnewbies-bounce@xxxxxxxxxxxx] On Behalf Of tyler@xxxxxxxx Sent: Wednesday, May 10, 2006 4:25 PM To: kernelnewbies@xxxxxxxxxxxx Subject: Re: Implementation of Virtual Memory on Linux On Wed, May 10, 2006 at 01:06:22PM +0530, Abhijit Pawar wrote: > Ideally OOM is the last resort in this case. Need to kill some other > application whose Pages are exhausting the SWAP. But, how that will be > decided? > > > Thanks. > -- > Abhijit. OOM stands for Out Of Memory. In the linux kernel, this problem is handled by the OOM manager, which simply does the following : check if there is enough memory avalaible, verify that the the system is truly out of memory and then selects a process to kill. The process to kill is selected by the function select_bad_process(). It tends to select a young process which takes a lot of memory. All these informations are extracted from the prefect mel gorman's book, Linux VM. You can find it (and you must read it:)) here : http://www.skynet.ie/~mel/projects/ The last chapter is about OOM. -- tyler tyler@xxxxxxxx ___________________________________________________________________________ Yahoo! Mail riinvente le mail ! Dicouvrez le nouveau Yahoo! Mail et son interface rivolutionnaire. http://fr.mail.yahoo.com -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/ -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
