Re: qemu needs > 2 GB of RAM to build?

[Joshua Lock <josh@linux.intel.com>]

On 18/11/11 12:24, Scott Garman wrote:
> On 11/18/2011 11:59 AM, Joshua Lock wrote:
>>
>>
>> On 18/11/11 11:49, Khem Raj wrote:
>>> On Fri, Nov 18, 2011 at 11:39 AM, Scott
>>> Garman<scott.a.garman@intel.com>  wrote:
>>>> Hi all,
>>>>
>>>> I'm testing building core-image-minimal in a resource-constrained
>>>> environment (a VirtualBox VM with 2300 MB of RAM allocated to it). With
>>>> PARALLEL_MAKE set to -j4 (the VM does have two CPUs allocated), I'm
>>>> finding
>>>> that the build of qemu-native fails because the OOM killer steps in and
>>>> kills gcc. This is happening during the linking phase of building qemu.
>>
>> What's BB_NUMBER_THREADS set to? I had to reduce to 1 to build
>> qemu-native on a laptop with 2GB RAM. iirc it had a habit of linking
>> something equally large such as eglibc, qt or the kernel at the same
>> time.
> 
> I had it set to 2, but I'm able to reproduce the problem when rebuilding
> *only* qemu-native.
> 
>>> what distro are you running on guest ? it could be something wrong
>>> with the distro gcc or system
>>
>> I've seen this on F14 (Gnome 2.x) and F15 (Gnome 3) with a laptop with
>> only 2GB RAM.
> 
> This is a Fedora 14 host running GNOME 2.x
> 
>> I think BB_NUMBER_THREADS is the key here. And whether you're running
>> much in the way of a desktop environment.
> 
> I would have thought PARALLEL_MAKE would have been more of the issue - I
> think I saw two instances of ld running via top when the crash occurred.

Both doing linking for qemu-native? I thought I remembered one giant
link phase but it's been a while.

> 
> In any case, the purpose behind this exercise for me is to test the
> feasibility of using a VM environment for performing builds. The idea is
> to get Windows users started with some tutorial screencasts they can
> follow along with using the VM until they feel compelled enough to set
> up a native Linux development system.
> 
> It sounds like a system requirement of using this VM will have to be
> that the host system have 6 GB or more of RAM (since the VM guest won't
> be able to use all of that - generally around 50-60%). This pretty much
> rules out its use on all but the most recent laptops.

Can you not include some canny sstate packages in the VM image? i.e
qemu-native?

Or work with qemu upstream to re-work the link phase?

Or both. One short-term and one long-term :-)

Cheers,

Joshua
-- 
Joshua Lock
        Yocto Project "Johannes factotum"
        Intel Open Source Technology Centre