Re: [BUG] Slow SATA disk - waiting in balance_dirty_pages() on i686-pae.html

From: Philipp Hahn
Date: Wed Aug 02 2017 - 10:57:19 EST


Hello,

Am 02.08.2017 um 14:29 schrieb Michal Hocko:
> On Tue 01-08-17 12:32:40, Philipp Hahn wrote:
>> ;TL,DR: apt-get is blocked by balance_dirty_pages() with linux-{3,16
>> 4.2, 4.9}, but fast after reboot.
>>
>>
>> We still have several systems running 4.9.0-ucs104-686-pae. They have 16
>> GiB RAM and two disk:
>
> I would strongly discourage you from using 32b system with so much
> memory. This will always bump into problems because of the inherent
> kernel/userspace split. Also I would bet that the problem you are seeing
> is the lack of lowmem memory which is considered for the dirty writers
> throttling unless you have vm.highmem_is_dirtyable is set to 1 which is
> not the case in your setup.

Thank you for the hint, I will give it a try.

Philipp