memory fragmentation issues in 1.2?

George Schlossnagle george at
Thu Dec 7 01:44:01 UTC 2006

Paul T wrote:
> --- George Schlossnagle <george at> wrote:
>> Paul T wrote:
>>> Turn off the OOM killer and see what happens?
>> I could.  I would expect it to actually OOM and die
>> when it exceeds
>> addressable memory space.
> All I'm saying is that it could be that OOM gets
> nervous too early. If I would post you the cacti
> pictures from my servers you would see than the amount
> of 'free RAM' goes down for a while. And then at some
> point Linux re-claims it. It's OK behaviour.

If malloc fails (fails to allocate), then it doesn't really matter if
you have the OOM killer running or not.

> Are you complaining about the amount of 'free RAM'
> going down on Linux? If that is what you call
> 'addressabe RAM' - I see no reason to be troubled.

I'm talking about the addressable memory space in my process shrinking.

> When was that? 
> A lot have changed in Linux codebase in last 10 years.

This year, against all the major Linux distro vendors.  Porting Solaris'
libumem to the platforms we needed to support and integrating against
that solved all the issues.

Having a discussion with you about whether the behavior I'm experiencing
is possible/real/a figment of my imagination doesn't really move me any
closer to solving my problem.


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