2023-07-13 16:04:40

by richard clark

Subject: Question about the 'bw' field in the fio output

Hi,

I found that sometimes the fio command will have an additional 'bw'
field as below:
...
clat percentiles (usec):
| 1.00th=[. 51]...
bw ( KiB/s): min=45689, max=49753, per=100.00%, avg=49658.56,
stdev=89.23, samples =5
iops : min=.....
...

Please there is a line beginning with 'bw ( KiB/s)...', but sometimes
the 'bw' line doesn't show, does anybody know the reasons?

Thanks.

2023-07-13 17:06:23

by Vincent Fu

Subject: Re: Question about the 'bw' field in the fio output

On 7/13/23 11:43, richard clark wrote:
> Hi,
>
> I found that sometimes the fio command will have an additional 'bw'
> field as below:
> ...
> clat percentiles (usec):
> | 1.00th=[. 51]...
> bw ( KiB/s): min=45689, max=49753, per=100.00%, avg=49658.56,
> stdev=89.23, samples =5
> iops : min=.....
> ...
>
> Please there is a line beginning with 'bw ( KiB/s)...', but sometimes
> the 'bw' line doesn't show, does anybody know the reasons?
>
> Thanks.

See:

https://lore.kernel.org/fio/[email protected]/T/#t

https://github.com/vincentkfu/fio-blog/wiki/Periodic-performance-measurements

2023-07-14 03:25:54

by richard clark

Subject: Re: Question about the 'bw' field in the fio output

The information is very very helpful, thank you Vincent !!

On Fri, Jul 14, 2023 at 12:44 AM Vincent Fu <[email protected]> wrote:
>
> On 7/13/23 11:43, richard clark wrote:
> > Hi,
> >
> > I found that sometimes the fio command will have an additional 'bw'
> > field as below:
> > ...
> > clat percentiles (usec):
> > | 1.00th=[. 51]...
> > bw ( KiB/s): min=45689, max=49753, per=100.00%, avg=49658.56,
> > stdev=89.23, samples =5
> > iops : min=.....
> > ...
> >
> > Please there is a line beginning with 'bw ( KiB/s)...', but sometimes
> > the 'bw' line doesn't show, does anybody know the reasons?
> >
> > Thanks.
>
> See:
>
> https://lore.kernel.org/fio/[email protected]/T/#t
>
> https://github.com/vincentkfu/fio-blog/wiki/Periodic-performance-measurements