Is my kernel still being low latency if updating it?

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Megver83
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Joined: 12/21/2015

Hi, I updated my kernel to the latest version, and I wanted to know if it was still low latency like the pre-installed ones.

# dpkg -l | grep linux-image
rc linux-image-3.13.0-39-lowlatency 3.13.0-39.66+7.0trisquel2 amd64 Linux kernel image for version 3.13.0 on 64 bit x86 SMP
ii linux-image-3.13.0-74-lowlatency 3.13.0-74.118+7.0trisquel2 amd64 Linux-libre kernel image for version 3.13.0
ii linux-image-4.4.0-gnu 4.4-gnu-1.0 amd64 Linux kernel, version 4.4.0-gnu
ii linux-image-lowlatency 3.13.0.74.80+7.0trisquel2 amd64 lowlatency Linux-libre kernel image

Magic Banana

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Joined: 07/24/2010

Yes, you are. Read the description of "linux-image-lowlatency":
This package will always depend on the latest lowlatency kernel image available.

jbar
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Joined: 01/22/2011

There's also linux-image-4.4.0-gnu installed, not only "linux-image-xxx-lowlatency" kernels.

Magic Banana

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Joined: 07/24/2010

You are right. I do not know how I could ignore it. It must be the kernel from http://linux-libre.fsfla.org/pub/linux-libre/freesh/

And it probably is the one that runs by default (unless GRUB_DEFAULT in /etc/default/grub was changed) because it is the latest one. The following command would tell:
$ uname -r

If you do not want this kernel, simply remove it; for instance using the "Synaptic package manager" in the "System settings". And the related repository can be removed from /etc/apt/sources.list too (here using Trisquel's default text editor):
$ gksu gedit /etc/apt/sources.list

Megver83
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Joined: 12/21/2015

Hi, I updated my kernel to the latest version, and I wanted to know if it was
still low latency like the pre-installed ones.

# dpkg -l | grep linux-image
rc linux-image-3.13.0-39-lowlatency 3.13.0-39.66+7.0trisquel2
amd64 Linux kernel image for version 3.13.0 on 64
bit x86 SMP
ii linux-image-3.13.0-74-lowlatency 3.13.0-74.118+7.0trisquel2
amd64 Linux-libre kernel image for version 3.13.0
ii linux-image-4.4.0-gnu 4.4-gnu-1.0
amd64 Linux kernel, version 4.4.0-gnu
ii linux-image-lowlatency 3.13.0.74.80+7.0trisquel2
amd64 lowlatency Linux-libre kernel image

Magic Banana

I am a member!

I am a translator!

Offline
Joined: 07/24/2010

You are right. I do not know how I could ignore it. It must be the kernel
from http://linux-libre.fsfla.org/pub/linux-libre/freesh/

And it probably is the one that runs by default (unless GRUB_DEFAULT in
/etc/default/grub was changed) because it is the latest one. The following
command would tell:
$ uname -r

If you do not want this kernel, simply remove it; for instance using the
"Synaptic package manager" in the "System settings". And the related
repository can be removed from /etc/apt/sources.list too (here using
Trisquel's default text editor):
$ gksu gedit /etc/apt/sources.list

jbar
Offline
Joined: 01/22/2011

There's also linux-image-4.4.0-gnu installed, not only
"linux-image-xxx-lowlatency" kernels.

Megver83
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Joined: 12/21/2015

OK, thanks. And by the way, what for is it separated from the kernel?

Magic Banana

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I am a translator!

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Joined: 07/24/2010

"linux-image-lowlatency" is a "meta-package": it does not install anything by itself and only exists to impose dependencies. In this case: the latest lowlatency kernel image available. Currently, it is linux-image-3.13.0-76-lowlatency. It was linux-image-3.13.0-74-lowlatency a few days ago. But both versions still are in the repository and can be installed in parallel.

In fact, when a new version is automatically proposed to you (thanks to the meta-package whose dependency is modified), installing the new kernel image does not replace the older version. In this way, if something goes wrong with the new kernel, you can still boot the older one. It also means you must remove by hand (using for instance the "Synaptic package manager" in the "System settings") the oldest kernels from time to time. Otherwise you end up filling up your root partition (or your /boot partition if it is separated from /) with kernels: just keep he latest one and the one before that if you haven' had any problem with it.

Magic Banana

I am a member!

I am a translator!

Offline
Joined: 07/24/2010

"linux-image-lowlatency" is a "meta-package": it does not install anything by
itself and only exists to impose dependencies. In this case: the latest
lowlatency kernel image available. Currently, it is
linux-image-3.13.0-76-lowlatency. It was linux-image-3.13.0-74-lowlatency a
few days ago. But both versions still are in the repository and can be
installed in parallel.

In fact, when a new version is automatically proposed to you (thanks to the
meta-package whose dependency is modified), installing the new kernel image
does not replace the older version. In this way, if something goes wrong with
the new kernel, you can still boot the older one. It also means you must
remove by hand (using for instance the "Synaptic package manager" in the
"System settings") the oldest kernels from time to time. Otherwise you end up
filling up your root partition (or your /boot partition if it is separated
from /) with kernels: just keep he latest one and the one before that if you
haven' had any problem with it.

Magic Banana

I am a member!

I am a translator!

Offline
Joined: 07/24/2010

Yes, you are. Read the description of "linux-image-lowlatency":
This package will always depend on the latest lowlatency kernel image
available.

Megver83
Offline
Joined: 12/21/2015

OK, thanks. And by the way, what for is it separated from the kernel?