Re: Re: [PATCH v7] io_uring: Statistics of the true utilization of sq threads.

[Xiaobing Li <xiaobing.li@samsung.com>]

On 1/18/24 19:34, Jens Axboe wrote:
>> diff --git a/io_uring/sqpoll.h b/io_uring/sqpoll.h
>> index 8df37e8c9149..c14c00240443 100644
>> --- a/io_uring/sqpoll.h
>> +++ b/io_uring/sqpoll.h
>> @@ -16,6 +16,7 @@ struct io_sq_data {
>>  	pid_t			task_pid;
>>  	pid_t			task_tgid;
>>  
>> +	long long			work_time;
>>  	unsigned long		state;
>>  	struct completion	exited;
>>  };
>
>Probably just make that an u64.
>
>As Pavel mentioned, I think we really need to consider if fdinfo is the
>appropriate API for this. It's fine if you're running stuff directly and
>you're just curious, but it's a very cumbersome API in general as you
>need to know the pid of the task holding the ring, the fd of the ring,
>and then you can get it as a textual description. If this is something
>that is deemed useful, would it not make more sense to make it
>programatically available in addition, or even exclusively?

Hi, Jens and Pavel
sorry for the late reply.

I've tried some other methods, but overall, I haven't found a more suitable 
method than fdinfo.
If you think it is troublesome to obtain the PID,  then I can provide
 a shell script to output the total_time and work_time of all sqpoll threads 
 to the terminal, so that we do not have to manually obtain the PID of each 
 thread (the script can be placed in tools/ include/io_uring).

eg:

PID    WorkTime(us)   TotalTime(us)   COMMAND
9330   1106578        2215321         iou-sqp-9329
9454   1510658        1715321         iou-sqp-9453
9478   165785         223219          iou-sqp-9477
9587   106578         153217          iou-sqp-9586

What do you think of this solution?