Brian Whitman wrote:
On Sun, Jan 4, 2009 at 9:47 PM, Mark Miller <markrmil...@gmail.com> wrote:
Hey Brian, I didn't catch what OS you are using on EC2 by the way. I
thought most UNIX OS's were using memory overcommit - A quick search brings
up Linux, AIX, and HP-UX, and maybe even OSX?
What are you running over there? EC2, so Linux I assume?
This is on debian, a 2.6.21 x86_64 kernel
Interesting. Well it must not be overcommitting then. I think thats your
only hope without a serious pain in the butt.
Check your settings - you should be able to do it through proc. Here is
a bit of info cut and pasted from the web. I am *guessing* that you are
in mode 0, and the Heuristic is worried you are going to try and use
that RAM. Perhaps try 1:
echo 1 > /proc/sys/vm/overcommit_memory
0 - Heuristic overcommit handling. Obvious overcommits of address
space are refused. Used for a typical system. It ensures a seriously
wild allocation fails while allowing overcommit to reduce swap usage.
root is allowed to allocate slighly more memory in this mode. This is
the default.
1 - Always overcommit.
2 - Don't overcommit. The total address space commit for the system
is not permitted to exceed swap plus a configurable percentage (default
is 50) of physical RAM. Depending on the percentage you use, in most
situations this means a process will not be killed while attempting to
use already-allocated memory but will receive errors on memory
allocation as appropriate.
