Re: [gentoo-user] Filesystem with lowest CPU load, acceptable emerge performance, and stable?

[Pandu Poluan <pandu@poluan.info>]

On Thu, Sep 8, 2011 at 05:15, kashani <kashani-list@badapple.net> wrote:
> On 9/7/2011 5:25 AM, Pandu Poluan wrote:
>>
>> Well, for all my other servers, I standardized on ext4.
>>
>> Since a vFirewall have to perform lots of packet-juggling, I'd rather
>> dedicate the CPU time to the kernel rather than the HD I/O.
>>
>> Of course, a vFirewall needs to be updated every now and then, but
>> everytime an update is called for, it should not overly tax the CPU
>> and degrade the netfilter framework.
>>
>> Rgds,
>
>        You are making my point for me, but not realizing the end result of
> the logic. There isn't any filesystem change that is going to affect CPU
> usage by more than a few percentage points in the use case you've described.
> Rsync, portage, and gcc use a massive amount of CPU compared to the amount
> the filesystem changes will use other than brief points during the rsync.
> Additionally most benchmarks are testing filesystem throughput and comparing
> it to CPU. Because disk IO isn't under pressure in your scenario you're
> unlikely to see the pathological use of CPU that can highlight the
> differences between filesystems.

Gosh, you're right! (And Jesús' reply also remind me).

What was I thinking >.<

>        That said, you have a few reasonable choices.
>
> 1. Move to a binary distro
> 2. Use buildpkg on a clone of this server and only install packages on your
> Firewall.
> 3. NFS mount /usr/portage when you need it and dist build on another server
> 4. Don't upgrade
> 5. Get a firewall server with more CPU so that it doesn't matter
> 6. Script a new firewall server install every x months and swap it into
> place and drop the original server.
> 7. Some combination of the above.
>

I think I'll do (6). Attach a HD to another VM, install a similar
system on that HD (chroot-ed, of course), update that regularly, make
a stage5 (or 6 or whatevs) of the (ch)root, then do a 'tar xJf' on the
firewall proper.

So, a different scenario, then: Sometimes I need to log stuffs (via
ULOG) or do a tcpdump. Will JFS give me additional benefit to ext4? Or
should I just stick with ext4?

Rgds,
-- 
FdS Pandu E Poluan
~ IT Optimizer ~

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