[OpenWrt-Devel] overcommit memory/ratio

[David Lang]

On Wed, 17 Sep 2014, Nikos Mavrogiannopoulos wrote:

> On Tue, 2014-09-16 at 22:29 +0000, Karl P wrote:
>> Alternatively, if you know which process it is, set it's oom_adj_score so that
>> it gets killed first.
>
>>   Some other people are kinda used to things behaving as
>> they are, for better or worse.  (Turning off overcommit on an openwrt device is
>> no different than turning off overcommit on a desktop as far as I'm concerned.
>> Somethings will be better, lots of things less so)
>
> Well being used to something bad, doesn't mean things cannot get better.
> Routers (to which I have some experience at), rarely have processes
> running that wouldn't matter if they are randomly killed; on a desktop
> system you immediately notice an issue, and you can reboot, a router is
> typically running unattended. Being locked out of such a system because
> another process had a memory leak, can be an issue.

Turning off overcommit so that a program that wants to spawn a child will end up 
requiring double it's memory (for the time between the fork and the exec) is 
likely to cause programs to fail when they don't need to.

And unlike desktops, you can't just say "allocate a lot of swap" to cover this 
up.

In spite of what some people say, it's far from a clear-cut win to disable 
overcommit.

David Lang
_______________________________________________
openwrt-devel mailing list
openwrt-devel at lists.openwrt.org
https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel