Re: freemem-slack and large memory environments

[Mike Latimer <mlatimer@suse.com>]

On Thursday, February 26, 2015 05:53:06 PM Stefano Stabellini wrote:
> What is the return value of libxl_set_memory_target and
> libxl_wait_for_free_memory in that case? Isn't it just a matter of
> properly handle the return values?

The return from libxl_set_memory_target is 0, as the assignment works just 
fine. I don't have the return from libxl_wait_for_free_memory in my notes, so 
I'll spin up another test and track that down.

> Or maybe we just need to change the libxl_set_memory_target call to use
> an absolute memory target to avoid restricting dom0 memory more than
> necessary at each iteration. Also increasing the timeout argument passed
> to the libxl_wait_for_free_memory call could help.

Using an absolute target would help, and would obviously only have to be set 
once - which is similar to what my patch did.

Increasing the timeout would help, but if the timeout were insufficient (say 
when dealing with very large guests), it wouldn't solve the problem.

-Mike