Re: 02/02: image: Disable compression for ISO images.

Re: 02/02: image: Disable compression for ISO images.

[Tobias Geerinckx-Rice]

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Mathieu,

guix-commits@gnu.org 写道：
> +   ;; XXX: Temporarily disable compression to speed-up the 
> tests.
> +   (compression? #f)))

Interesting!  What kind of improvement do you see, roughly?

When I added zlib compression I was surprised to learn that here 
it made no significant difference in wall clock time (less than a 
minute; 5% or so) or CPU time.  The disks they spin and CPU she is 
fast, but still I would have noticed a spike.

Kind regards,

T G-R

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Re: 02/02: image: Disable compression for ISO images.

[Mathieu Othacehe]

Hey Tobias,

> guix-commits@gnu.org 写道：
>> +   ;; XXX: Temporarily disable compression to speed-up the tests.
>> +   (compression? #f)))
>
> Interesting!  What kind of improvement do you see, roughly?

I posted some figures here:
https://lists.gnu.org/archive/html/guix-devel/2020-04/msg00374.html.

Here's a more complete summary:

--8<---------------cut here---------------start------------->8---
|                | Host (wip-disk-image) | VM (master) |
|----------------+-----------------------+-------------|
| No compression | 4min                  | 12min       |
| Compression    | 8min                  | 19min       |
--8<---------------cut here---------------end--------------->8---

> When I added zlib compression I was surprised to learn that here it made no
> significant difference in wall clock time (less than a minute; 5% or so) or
> CPU time.  The disks they spin and CPU she is fast, but still I would have
> noticed a spike.

Strange we have different results, those benches are not very accurate
though.

Thanks,

Mathieu

Re: 02/02: image: Disable compression for ISO images.

[Bengt Richter]

On +2020-04-27 18:00:05 +0200, Mathieu Othacehe wrote:
> 
> Hey Tobias,
> 
> > guix-commits@gnu.org 写道：
> >> +   ;; XXX: Temporarily disable compression to speed-up the tests.
> >> +   (compression? #f)))
> >
> > Interesting!  What kind of improvement do you see, roughly?
> 
> I posted some figures here:
> https://lists.gnu.org/archive/html/guix-devel/2020-04/msg00374.html.
> 
> Here's a more complete summary:
> 
> --8<---------------cut here---------------start------------->8---
> |                | Host (wip-disk-image) | VM (master) |
> |----------------+-----------------------+-------------|
> | No compression | 4min                  | 12min       |
> | Compression    | 8min                  | 19min       |
> --8<---------------cut here---------------end--------------->8---
> 
> > When I added zlib compression I was surprised to learn that here it made no
> > significant difference in wall clock time (less than a minute; 5% or so) or
> > CPU time.  The disks they spin and CPU she is fast, but still I would have
> > noticed a spike.
> 
> Strange we have different results, those benches are not very accurate
> though.

Might it throw some light to see your different results for
--8<---------------cut here---------------start------------->8---
$ lscpu|grep -i bogo
$ top -n1|grep ^MiB
--8<---------------cut here---------------end--------------->8---
At least I'm curious :)

> 
> Thanks,
> 
> Mathieu
> 

-- 
Regards,
Bengt Richter