No. Actually, after some retests my observation is that it happens 
regardless the thread is pinned or not.
So, 

When thread *T* is pinned to CPU #10 and the task interval is set to 1ms, 
the average task execution time is *100 µs*. However, when the task 
interval is increased to 40ms on the same pinned core, the average 
execution time significantly degrades to *250 µs*. If T is not pinned, the 
result is same.


piątek, 13 lutego 2026 o 18:39:03 UTC+1 Mark E. Dawson, Jr. napisał(a):

> Do you have a baseline for how your isolated core should perform using a 
> tool like 'osnoise'?
>
> On Friday, February 13, 2026 at 10:18:49 AM UTC-6 [email protected] wrote:
>
>> Hi,
>>
>> let's look at the example:
>>
>> The system is running with the following kernel parameters: 
>>
>> isolcpus=10, nohz_full=10, nohz=on, idle=poll, intel_pstate=disable. 
>>
>> We have a thread *T* that uses Thread.onSpinWait() while polling a 
>> lock-free shared queue. In this context, the *task interval* refers to 
>> the time elapsed between adding consecutive tasks to the queue.
>>
>> When thread *T* is pinned to CPU #10 and the task interval is set to 
>> 1ms, the average task execution time is *100 µs*. However, when the task 
>> interval is increased to 40ms on the same pinned core, the average 
>> execution time significantly degrades to *250 µs*.
>>
>> In contrast, when thread *T* is unpinned, the performance remains much 
>> more consistent. At a 1ms task interval, the average execution time is *110 
>> µs*, and it only slightly increases to *120 µs* when the interval is 
>> extended to 40ms.
>>
>

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