how can i limit system resources for a particular process?

hi everyone,
let's say i want to create an .img file of 50GB with "dd" command. After
that, i will give it a format with mkfs.ext3.
The problem is that while "dd" is running I'm not able to do anything
else on the machine, not even ssh in, it just consumes all the available
resources, and as I'm creating a 50GB image, i can't access the machine
for several minutes.
I've tried to use "nice" command, giving the "dd" process the lowest
possible priority, 19. The thing is that the whole thing performs
better, i can establish ssh connection. However, i can't do much when
I'm in it, everything is so slow.
I've also read some documentation about "limit/ulimit" command, but i
fail to see how i can use it successfully for this matter.
I would like to run dd and let it use, for example, only 10% of the CPU
time or 30% of the total amount of memory. Is that possible? I'm not
looking for a "general" process limit for the whole system, only for a
particular process.
Thanks in advance for your help.
--
kubuntu-users mailing list
kubuntu-users@lists.ubuntu.com
Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/kubuntu-users

Jordi Moles Blanco wrote:
> let's say i want to create an .img file of 50GB with "dd" command.
> After that, i will give it a format with mkfs.ext3.
>
> The problem is that while "dd" is running I'm not able to do anything
> else on the machine, not even ssh in, it just consumes all the
> available resources, and as I'm creating a 50GB image, i can't access
> the machine for several minutes.
>
> I've tried to use "nice" command, giving the "dd" process the lowest
> possible priority, 19. The thing is that the whole thing performs
> better, i can establish ssh connection. However, i can't do much when
> I'm in it, everything is so slow.
Try the ionice command. In your case the problem is the constant write
access to the disk. If you want to limit disk access to times where no
other process wants to use the disk, it would be a command like this:
ionice -c3 dd if=/dev/zero of=filename.img bs=10M count=5000
You can even combine it with nice like
nice -19 ionice -c3 dd if=/dev/zero of=filename.img bs=10M count=5000
but I don't think that is necessary.
Nils
--
kubuntu-users mailing list
kubuntu-users@lists.ubuntu.com
Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/kubuntu-users

On Thursday, 02 July 2009 17:31:41 Nils Kassube wrote:
> Try the ionice command
Awesome post Nils, thanks. I made a gnote of it ;)
\d
--
kubuntu-users mailing list
kubuntu-users@lists.ubuntu.com
Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/kubuntu-users

This is an OpenPGP/MIME signed message (RFC 2440 and 3156)
--------------enigA912562516621608B1554991
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
Donn wrote:
> On Thursday, 02 July 2009 17:31:41 Nils Kassube wrote:
>> Try the ionice command
> Awesome post Nils, thanks. I made a gnote of it ;)
>=20
> \d
>=20
yeah, nice one. in kysyguard, it automatically redjusts the IO niceness
as i move the CPU niceness slider. but for a non-gui way, ionice is
excellent. thanks!
--=20
Willy K. Hamra
Manager of Hamra Information Systems
Co. Manager of Zeina Computer & Billy Net
--------------enigA912562516621608B1554991
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: OpenPGP digital signature
Content-Disposition: attachment; filename="signature.asc"
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.9 (GNU/Linux)
Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org
iEYEARECAAYFAkpM1d0ACgkQOO35WNta+yRiMQCgjjtfgNoUNzRthjw07av0X8gA
u/YAoJLDu3ObOyeU6h91tKq8yHj06Rwe
=UBAH
-----END PGP SIGNATURE-----
--------------enigA912562516621608B1554991--

On Thursday 02 July 2009 17:38:40 Donn wrote:
> On Thursday, 02 July 2009 17:31:41 Nils Kassube wrote:
> > Try the ionice command
>
> Awesome post Nils, thanks. I made a gnote of it ;)
I agree, but I used kjots ;-)
--
kubuntu-users mailing list
kubuntu-users@lists.ubuntu.com
Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/kubuntu-users

hi,
thanks for the advice, that worked great, it's what i was looking for.
Jordi.
En/na Nils Kassube ha escrit:
> Jordi Moles Blanco wrote:
>
>> let's say i want to create an .img file of 50GB with "dd" command.
>> After that, i will give it a format with mkfs.ext3.
>>
>> The problem is that while "dd" is running I'm not able to do anything
>> else on the machine, not even ssh in, it just consumes all the
>> available resources, and as I'm creating a 50GB image, i can't access
>> the machine for several minutes.
>>
>> I've tried to use "nice" command, giving the "dd" process the lowest
>> possible priority, 19. The thing is that the whole thing performs
>> better, i can establish ssh connection. However, i can't do much when
>> I'm in it, everything is so slow.
>>
>
> Try the ionice command. In your case the problem is the constant write
> access to the disk. If you want to limit disk access to times where no
> other process wants to use the disk, it would be a command like this:
>
> ionice -c3 dd if=/dev/zero of=filename.img bs=10M count=5000
>
> You can even combine it with nice like
>
> nice -19 ionice -c3 dd if=/dev/zero of=filename.img bs=10M count=5000
>
> but I don't think that is necessary.
>
>
> Nils
>
>
>
--
kubuntu-users mailing list
kubuntu-users@lists.ubuntu.com
Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/kubuntu-users