Re: [PATCH 0/3] ipmi: msghandler: check the users and msgs causing the system to block

[chenchacha <chen.chenchacha@foxmail.com>]

On 2022/3/28 23:45, Corey Minyard wrote:
> On Mon, Mar 28, 2022 at 11:27:06PM +0800, chenchacha wrote:
>>
>>> Anyway, a better solution for the kernel side of things, I think, would
>>> be to add limits on the number of users and the number of messages per
>>> user.  That's more inline with what other kernel things do.  I know of
>>> nothing else in the kernel that does what you are proposing.
>>
>> The precondition for add limits, is that people known that ipmi has too many
>> users and messages cause problems, this patch is to let administrator known
>> that.
>>
>> In addition, different machines have different limit, My server my block
>> 700,000 messages and it's fine, and my NAS pc went to OOM when it probably
>> blocked for 10,000 messages. So, to limit the number of users and messages,
>> can wait until we have accumulated some online experience?
> 
> I don't mean a limit on the total number of messages, but a limit on the
> total number of oustanding messages, and a limit on the total number of
> users.  No user should have more than a handful of oustanding message,
> and limiting the number of users to 20 or 30 should be more than enough
> for any system.
> 
> Having those limits in place would probably help you trace down your
> problem, as you would hit the limits and it should report it at the
> source of the problem.
> 
> -corey

Hi Corey:

According to your suggestion, I have don some tests. After adding 
limits, event if the bmc hardware fails, the ipmi will not occupy a 
large memory in system.

The modifications are in the next version of the patch.

Thanks
--
Chen Guanqiao