Re: [RFC PATCH 0/3] Cgroup-based THP control

[Stepanov Anatoly]

On 11/1/2024 4:28 PM, Michal Hocko wrote:
> On Fri 01-11-24 16:24:55, Stepanov Anatoly wrote:
>> On 11/1/2024 4:15 PM, Michal Hocko wrote:
>>> On Fri 01-11-24 14:54:27, Stepanov Anatoly wrote:
>>>> On 11/1/2024 10:35 AM, Michal Hocko wrote:
>>>>> On Thu 31-10-24 17:37:12, Stepanov Anatoly wrote:
>>>>>> If we consider the inheritance approach (prctl + launcher), it's fine until we need to change
>>>>>> THP mode property for several tasks at once, in this case some batch-change approach needed.
>>>>>
>>>>> I do not follow. How is this any different from a single process? Or do
>>>>> you mean to change the mode for an already running process?
>>>>>
>>>> yes, for already running set of processes
>>>
>>
>>> Why is that preferred over setting the policy upfront?
>> Setting the policy in advance is fine, as the first step to do.
>> But we might not know in advance
>> which exact policy is the most beneficial for one set of apps or another.

> 
> How do you plan to find that out when the application is running
> already?
For example, if someone willing to compare some DB server performance with THP-off vs THP-on,
and DB server restart isn't an option.
Of course, if the restart is ok then we don't need such feature, "launcher" approach would be enough.
if i got your question right.


-- 
Anatoly Stepanov, Huawei