[yocto] Fwd: build failure on ubuntu 64bits development system

[Darren Hart]

On 01/19/2012 05:55 AM, Jim Abernathy wrote:
> On 01/18/2012 04:34 PM, Darren Hart wrote:
>>
>> On 01/18/2012 09:05 AM, Jim Abernathy wrote:
>>
>>> FYI for those wanting to use Soft RAID, make sure you create one very 
>>> small primary partition for GRUB2 to put the second part of the 
>>> boot-loader in.  Can't use the old process.
>> I strongly recommend using a separate DISK for your OS installation.
>> Yocto builds are hard on disks, and RAID 0 increases your risk of
>> failure in exchange for the added performance. I use a small SSD for my
>> OS disk and a large RAID0 array of spinning disks for /build and another
>> array for /virt (where my VM images live - easily recreated).
>>
> Learned a few things in this process. I appreciate all the help and advice.
> 
>  1. So we know that at least with Edison, btrfs does not work with bitbake.
>  2. When I rebuilt the system, this time I put the Linux root directory
>     on an 80GB SSD.  That is where I also have my clone of Linux-Yocto
>     repository, poky, and download directory , DL_DIR.
>  3. I have create /build with EXT4 format on a Software RAID 0 (striped)
>     partition, using 2 separate hard drives,  to use as the working
>     build directory for bitbake. I have a striped swap file on the same
>     two drives.  But with 8GB or RAM, I shouldn't be using that much.
> 
> My build times for some of the basic meta-intel BSPs is around 103 minutes.

You may be able to improve upon that with the following in /etc/fstab:

/dev/md0  /build  ext4  noauto,noatime,nodiratime,commit=6000  0  2

This reduces the number of writes due to updated access time and
increases the commit interval so it doesn't stall while writing out
every 5 minutes per default.

NOTE: THIS INCREASES YOUR RISK OF DATA LOSS

If your machine goes down during a build, you should plan on formatting
that drive. If you only keep builds on it, they easily recreateable and
you may find the performance boost is worth the risk.

-- 
Darren Hart
Intel Open Source Technology Center
Yocto Project - Linux Kernel