On 3 March 2016 at 16:22, Michal Hocko <mhocko@xxxxxxxxxx> wrote:
On Thu 03-03-16 10:23:03, Jerry Lee wrote:
> On 3 March 2016 at 01:36, Michal Hocko <mhocko@xxxxxxxxxx> wrote:
>
> > On Wed 02-03-16 14:20:38, Jerry Lee wrote:
[...]
> > > Is there anything I could do to totally get rid of the problem?
> >
> > I would try to sacrifice those few megs and get rid of zone normal
> > completely. AFAIR mem=4G should limit the max_pfn to 4G so DMA32 should
> > cover the shole memory.
> >
>
> I came up with a patch that seem to work well on my system. But, I
> am afraid that it breaks the rule that all zones must be balanced for
> order-0 request and It may cause some other side-effect? I thought
> that the patch is just a workaround (a bad one) and not a cure-all.
One thing I haven't noticed previously is that you are running on the 3.12
kernel. I vaguely remember there were some fixes for small zones. Not
sure it would work for such a small zone but it would be worth trying I
guess. Could you retest with 4.4?
Hi,
Thanks for the quick feedback!
Before sending a mail to linux-mm, I found that there were discussions and
fixes for the small zone as you remember: https://lkml.org/lkml/2011/6/24/161 .
fixes for the small zone as you remember: https://lkml.org/lkml/2011/6/24/161 .
However, the fixes is kind of old and should be already included into the
current kernel version. Speaking of retesting the issue with kernel-4.4, it's
a bit hard for my right now because there are some customized hardware and
drivers on my system but I could give it a try.
BTW, there are some information I forgot to mention before. Originally, I use
kernel-3.4 on my system without the kswapd issue. After upgrading to
kernel-3.4 on my system without the kswapd issue. After upgrading to
linux-3.12.x, the issue occur. In addition, I found that there are other people
encountering the same problem even linux-4.x are used. [1] The idea to
increase the value of min_free_kbytes comes from the post. [1]
Anyway, thanks again for your help and suggestion!
- Jerry
--
Michal Hocko
SUSE Labs