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LiveOS installs, /dev/loop1 100% CPU

I've filed a bug about this, but I'm not sure what else to test or add
to demonstrate where the problem is coming from. It's some combination
of squashfs + ext4 overhead I'm guessing, but then also the perf
report output on the pid for loop1 shows lzma is the top consumer by a
long shot.

So it seems like xz has a considerable performance/resource impact here as well.

<a href="https://bugzilla.redhat.com/show_bug.cgi?id=1717728" title="https://bugzilla.redhat.com/show_bug.cgi?id=1717728">https://bugzilla.redhat.com/show_bug.cgi?id=1717728</a>

Comments

Re: LiveOS installs, /dev/loop1 100% CPU

By Zbigniew =?utf-... at 06/06/2019 - 06:45

On Wed, Jun 05, 2019 at 10:48:32PM -0600, Chris Murphy wrote:
Yep, that's reasonable. E.g. on my machine, decompressing code compressed
with xz -2 reads the compressed data at ~13MB/s. If the part of the live CD
that needs to be read to boot to a graphical environment is on the
order of 1GB, just decompressing that is going to take more than a
minute of CPU.

Zbyszek