Comment # 5 on bug 1194739 from Dominique Leuenberger

Last rebuild attempt (tried a few rebuilds)
https://build.opensuse.org/package/statistics/openSUSE:Factory:PowerPC/Mesa-drivers/standard/ppc64

Claims < 5GB of RAM; that's a huge variation (it used -j 8)

This usage was on worker obs-power8-01:4, which has
    <processors>20</processors>
    <jobs>8</jobs>
    <memory>8192</memory>
    <swap>2048</swap>
    <disk>20480</disk>


The one where we consumed the 11G was:
obs-power8-01:4

    <processors>20</processors>
    <jobs>16</jobs>
    <memory>11264</memory>
    <swap>2048</swap>
    <disk>51200</disk>

(so that ran -j 16)

Based on this, we seem to be able to deduct that ~ 750MB per core might be
about the value we'd need for limit_build.

On worker 8-01:4, this would then do 11264/750 => 15 (which would mean we were
really close to the limit); the 8GB worker would allow up to 10 threads, but
the box is limited to 8 anyway, so that's what'd be used there