[Cooker] [RFC] Enabling HIGHMEM support on kernel desktop586

[Herton Ronaldo Krzesinski]

Hi,

currently on kernel-desktop586 HIGHMEM is disabled, mainly because there is
some slightly overhead with it enabled and this kernel was meant for old
machines with low memory. But the desktop586 is used on Mandriva One (to work
on most hardware as possible, even the older ones and not 686 compatible arch
cpus), and we get many reports of it not detecting all memory available,
because systems with more than 896MB are very common today.

I measured recently the boot time of a geode with 512MB with highmem4g
enabled/nohighmem and didn't notice a significant difference at least on boot
time (the difference was around 1s or less, still in some error margin). So
what about we rediscuss this again and now enable CONFIG_HIGHMEM4G also on
desktop586 kernel? I think that there are more benefits in enabling it.

--
[]'s
Herton

[Anssi Hannula-3]

Herton Ronaldo Krzesinski wrote:

> Hi,
>
> currently on kernel-desktop586 HIGHMEM is disabled, mainly because there is
> some slightly overhead with it enabled and this kernel was meant for old
> machines with low memory. But the desktop586 is used on Mandriva One (to work
> on most hardware as possible, even the older ones and not 686 compatible arch
> cpus), and we get many reports of it not detecting all memory available,
> because systems with more than 896MB are very common today.
>
> I measured recently the boot time of a geode with 512MB with highmem4g
> enabled/nohighmem and didn't notice a significant difference at least on boot
> time (the difference was around 1s or less, still in some error margin). So
> what about we rediscuss this again and now enable CONFIG_HIGHMEM4G also on
> desktop586 kernel? I think that there are more benefits in enabling it.

As I brought this up in IRC, obviously +1 from here.

--
Anssi Hannula

[Sergio Rafael Lemke]

On Friday 04 July 2008 14:45:42 Anssi Hannula wrote:

> Herton Ronaldo Krzesinski wrote:
> > Hi,
> >
> > currently on kernel-desktop586 HIGHMEM is disabled, mainly because there
> > is some slightly overhead with it enabled and this kernel was meant for
> > old machines with low memory. But the desktop586 is used on Mandriva One
> > (to work on most hardware as possible, even the older ones and not 686
> > compatible arch cpus), and we get many reports of it not detecting all
> > memory available, because systems with more than 896MB are very common
> > today.
> >
> > I measured recently the boot time of a geode with 512MB with highmem4g
> > enabled/nohighmem and didn't notice a significant difference at least on
> > boot time (the difference was around 1s or less, still in some error
> > margin). So what about we rediscuss this again and now enable
> > CONFIG_HIGHMEM4G also on desktop586 kernel? I think that there are more
> > benefits in enabling it.
>
> As I brought this up in IRC, obviously +1 from here.

I can't count how many users i send from IRC to the wiki errata page to learn
how to change for a kernel with high mem. support.
+1

Sergio Rafael Lemke
Mandriva QA

[Adam Williamson-4]

On Fri, 2008-07-04 at 13:30 -0300, Herton Ronaldo Krzesinski wrote:

> Hi,
>
> currently on kernel-desktop586 HIGHMEM is disabled, mainly because there is
> some slightly overhead with it enabled and this kernel was meant for old
> machines with low memory. But the desktop586 is used on Mandriva One (to work
> on most hardware as possible, even the older ones and not 686 compatible arch
> cpus), and we get many reports of it not detecting all memory available,
> because systems with more than 896MB are very common today.
>
> I measured recently the boot time of a geode with 512MB with highmem4g
> enabled/nohighmem and didn't notice a significant difference at least on boot
> time (the difference was around 1s or less, still in some error margin). So
> what about we rediscuss this again and now enable CONFIG_HIGHMEM4G also on
> desktop586 kernel? I think that there are more benefits in enabling it.

I would be in favour of this.
--
adamw

[Herton Ronaldo Krzesinski]

Em Friday 04 July 2008 13:30:48 Herton Ronaldo Krzesinski escreveu:

> Hi,
>
> currently on kernel-desktop586 HIGHMEM is disabled, mainly because there is
> some slightly overhead with it enabled and this kernel was meant for old
> machines with low memory. But the desktop586 is used on Mandriva One (to
> work on most hardware as possible, even the older ones and not 686
> compatible arch cpus), and we get many reports of it not detecting all
> memory available, because systems with more than 896MB are very common
> today.
>
> I measured recently the boot time of a geode with 512MB with highmem4g
> enabled/nohighmem and didn't notice a significant difference at least on
> boot time (the difference was around 1s or less, still in some error
> margin). So what about we rediscuss this again and now enable
> CONFIG_HIGHMEM4G also on desktop586 kernel? I think that there are more
> benefits in enabling it.

Given all feedback and this, I enabled now CONFIG_HIGHMEM4G for desktop586
kernel, this modification will be available in next cooker kernels (post
2.6.26-0.rc8.1mnb-1-1mnb1).

--
[]'s
Herton