
Super Fast Local Workloads with LXD, ZFS, and Juju - mitechie
http://www.jorgecastro.org/2016/02/12/super-fast-local-workloads-with-juju/
======
smartbit
For those interested, please find here [1] the recordings of Juju sessions
(day 2 & 3 only) at Config Management Camp. Mark Shuttleworth's keynote is
also recorded [2]. Recording of James Page's presentation [3] "Building a
private cloud with the OpenStack charms" (day 1) might be available on the
Ubuntu youtube channel [4] next month.

[1]
[https://www.youtube.com/playlist?list=PLzSGDpUWtiotngRgVqpa8...](https://www.youtube.com/playlist?list=PLzSGDpUWtiotngRgVqpa8jeCBQ2CCjzfo)

[2]
[https://www.youtube.com/watch?v=sp_Re8Mx9xk#t=1h8m15s](https://www.youtube.com/watch?v=sp_Re8Mx9xk#t=1h8m15s)

[3]
[http://cfgmgmtcamp.eu/schedule/speakers/JamesPage.html](http://cfgmgmtcamp.eu/schedule/speakers/JamesPage.html)

[4]
[https://www.youtube.com/user/celebrateubuntu](https://www.youtube.com/user/celebrateubuntu)

~~~
smartbit
James Page's presentation came available at
[https://www.youtube.com/watch?v=pGeSxIB3KzY](https://www.youtube.com/watch?v=pGeSxIB3KzY)
published at [4]
[https://www.youtube.com/c/jujucharms](https://www.youtube.com/c/jujucharms)

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hoistor
I don't think the author of this post really understands ZFS.

Is that a 4 disk mirror? You'd be much faster using a raid10 there.

ZFS 'cache' devices are't for write cache either, you'd want a log device for
write perf reasons if that's your constraint... Even then it's unlikely to
make a difference on a workstation workload with 16GB of memory..

~~~
justinsaccount
Yeah.. it is a subtle difference between

    
    
      zpool create home mirror a b c d cache e
    

and

    
    
      zpool create home mirror a b mirror c d cache e

~~~
dr_zoidberg
Could you elaborate on the semantics of "cache"? I do understand the mirror
keyword, but I know next to nothing about ZFS and don't really get what
"cache" means, considering bouth your and OPs comment.

~~~
clord
a cache drive is l2arc. Brendan Gregg's post[0] explains it well, but the TLDR
is that l2arc is very much like an l2 cache in a cpu. Recent and relevant
items are held on a fast drive in case it will be needed in the near future.
It is really an L2 cache: L1 is called ARC and is held in dram.

If I recall correctly, the extra indexes and tags mean l2arc requires more
memory to work efficiently.

[0]:
[https://blogs.oracle.com/brendan/entry/test](https://blogs.oracle.com/brendan/entry/test)

~~~
semi-extrinsic
When your "medium-sized test server" has 128 GB RAM and half a TB worth of
SSDs... in 2008! Damn.

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matt_wulfeck
LXD is great. It lowers significantly the mental burden of running something
in containers because they behave essentially like a VM. That being said LXD
and juju are very Ubuntu things. LXD needs wide adoption for it to be
attractive as a serious workload.

~~~
pekk
If you like LXD, why can't you just use it and not care whether Redhat is
using it?

~~~
unethical_ban
Many organizations use RHEL, and individual workers cannot just spin up Ubuntu
for their bank database servers.

~~~
pekk
I guess we should all give up and only use what RHEL provides to us, then,
since it is the only universally available distribution.

~~~
unethical_ban
Your sarcasm is missing the point.

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markramm
This is a great development experience for distributed software. I'm really
looking forward to Ubuntu 16.10 -- a lot of things seem to be coming together
there.

~~~
sparkiegeek
Oh? I'm sure 16.10 will be great but there's a bunch of things coming in 16.04
which have me excited!

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z3t4
LXD looks sweet, and seem to have many advantages over Docker. The only issue
I got with it is the network settings where I miss a configuration that let me
isolate the containers from the LAN, while still giving them Internet access.

~~~
tyingq
The default setup for LXD is to create a NAT bridge which is what you seem to
be asking for.

Maybe something went wrong with your install?

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roozbeh18
if you want to try LXD Demo [https://linuxcontainers.org/lxd/try-
it/](https://linuxcontainers.org/lxd/try-it/)

Youtube
[https://www.youtube.com/watch?v=B_vRmItDORo](https://www.youtube.com/watch?v=B_vRmItDORo)

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cm3
Seeing how much it's used there, I wish ZFS would land in
linux(-next/-staging) already :-).

~~~
marcoceppi
We'll, it'll be in Ubuntu 16.04 :)

~~~
pritambaral
This is because of Debian's recent announcement about packaging ZFS, right? Or
is more work involved in getting ZFS into Xenial?

