<div class="gmail_quote">On Fri, Jul 13, 2012 at 11:19 AM, Andrea Adami <span dir="ltr"><<a href="mailto:andrea.adami@gmail.com" target="_blank">andrea.adami@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div class="im">On Fri, Jul 13, 2012 at 8:45 AM, Koen Kooi <<a href="mailto:koen@dominion.thruhere.net">koen@dominion.thruhere.net</a>> wrote:<br>
><br>
> Op 12 jul. 2012, om 21:22 heeft Saul Wold het volgende geschreven:<br>
><br>
>> On 07/12/2012 11:58 AM, Koen Kooi wrote:<br>
>>> Any volunteers to test this on a system with >4 real cores?<br>
>>><br>
>><br>
>> Koen,<br>
>><br>
>> Does OE-Core or Poky have an image setup for using .xz by default?<br>
><br>
> No, and as you can see from Andrei's patches, it would have never worked :)<br>
><br>
> regards,<br>
><br>
> Koen<br>
><br>
<br>
</div>This leads to a similar remark for lzma:<br>
<br>
The xz/lzma have been added with commit 38334ac and at that time both<br>
where using XZ_COMPRESSION_LEVEL.<br>
<br>
The code has been refactored afterwards and what happened is that lzma<br>
now defaults to compression 7 (the default) while xz is way too high<br>
(default is 6).<br>
<br></blockquote><div><br></div><div>Nope. It's default value is -9.</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
There is a well hidden pitfall with that, being that any image,<br>
including the initramfs, will use that compression factor.<br>
<br>
As you can notice in that (old) man xz [2] the memory requirements<br></blockquote><div><br></div><div>What old version?</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
are very high and what did happen to me was that the cpio.lzma could<br>
not be decompressed thus kernel could not boot (we override now the<br>
value setting "-e2" in our BSP).<br>
<br></blockquote><div> </div><div>Without threads, memory demand was around 700mb. So it should be ok for most of machines. </div><div><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Adding more threads will multiply that figures.<br>
<br></blockquote><div><br></div><div>Indeed. With 8GB memory at my disposal i couldn't compress an image with -e -9 and -T 0 (-T 4)/</div><div><br></div><div>@g</div></div>