Re: Why task_struct slab can't be released back to buddy system?

[Zhang Zhen <zhenzhang.zhang@huawei.com>]

On 2015/4/29 18:58, Rasmus Villemoes wrote:
> On Wed, Apr 29 2015, Zhang Zhen <zhenzhang.zhang@huawei.com> wrote:
> 
>> Hi,
>>
>> Our x86 system has crashed because oom.
>> We found task_struct slabs ate much memory.
> 
> I can't explain what you've seen, but a simple way to reduce the
> memory footprint of struct task_struct is
> 
> CONFIG_LATENCYTOP=n
> 
> That will reduce sizeof(struct task_struct) by ~3840 bytes (60%, give or
> take).
> 
Thank you for your sugesstion.

But my purpose is not to reduce sizeof(struct task_struct).
I want to know why the task_struct slab can't be released back
to buddy when the page's inuse is 0.

Best regards!
> Rasmus
> 
>> CACHE    	  NAME                 OBJSIZE  ALLOCATED     TOTAL  SLABS  SSIZE          //**Slabs is much larger than alloctated object counts**
>> ffff88081e007500 task_struct             6528       4639    229775  45955    32k
> 
> 


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