[geeks] solaris questions

[Shannon Hendrix]

On Apr 5, 2008, at 12:28 , Joshua Boyd wrote:

> I haven't seen any install choice for that.  I think you can boot in  
> single user mode and move stuff around after the initial install,  
> but I haven't tried moving all of var or usr, only sub directories  
> under them.

I don't really care about booting from ZFS, just running /usr, /var, / 
opt, and /u on it.

In other words, I'm fine with / on UFS, I'd just like the flexibility  
of changing the sizes of the others if I need to and otherwise easily  
managing them.

The ability to grow and shrink filesystems would make it easier to  
pick multiple mount points instead of just making one bit one to be  
sure everything fit, or create others as-needed.

I used to do this with Linux and its volume management and it was nice  
to have the option.

 From what I have read of the procedure for getting ZFS in place for  
your OS drive, I don't know if I have the time to put into it.

I'm already nervous about using ZFS as it is.

>> How do you run ZFS on hardware RAID?  In the future I am thinking  
>> of a nice 3Ware RAID card.  I like the hardware RAID because it  
>> reduces the overhead bandwidth and so far I've found the good cards  
>> very fast, even some cheaper ones.
>
> I think it would be worth benchmarking it both ways.

Only if your host is faster than your RAID card.

It's a physical fact that hardware RAID reduces host bus bandwidth.

The RAID operations occur on the controller, not your host bus.

If the controller is a good one, it effectively eliminates RAID  
overhead.

Even if your computer could do it faster, it might be useful to still  
use hardware RAID if you also have another heavy host bus user.

> I believe that running ZFS on a hardware raid is just like running  
> it on a single drive.  It seems to me that this must be supported  
> for ZFS to work correctly on a SAN.

Yeah, I thought so... helps to think out loud though.

I have read that ZFS has a serious bug where if it cannot write to a  
pool, it doesn't
handle the error and the kernel panics.

It is said to happen more often on SAN hardware, and RAID controllers  
which can take drives offline for maintenance, repair, reset, etc.

Supposedly the fix is coming in the next Solaris release, but Sun has  
known about it for a long time.

I'm a little worried that Sun didn't issue a fix when they first knew  
about it, but it should not affect the majority of users.

> I think that installing SunStudio on the main OS is the best bet.   
> For things that just won't work with it, I'm thinking to stick GCC  
> in a zone dedicated just to compiling stuff with GCC>

That might be a plan.  Have a "pkgsrc" zone to prevent polluting the  
global zone and new zones.  Transfer created packages to whichever  
zone I need.

What's the easiest way to determine the size of a zone.  All of mine  
say 5GB, which is obviously wrong, if I just use du on the zone  
directory.

> I just put up with N copies, although I don't have multiple copies  
> of anything as large as Apache.

Yeah... hmmm...

It just seems like the package systems for Solaris could cooperate and  
let you have just one system.

Maybe Sun should sponsor one package system and get a lot of people to  
contribute.

They don't seem much interested in it though.

I'll probably just put up with the pain and eventually forget about it.

80GB is pretty much the minimum for your "OS" drive these days... :)

Aside: I looked into getting a flash drive, disk-on-module for the IDE  
port.

Ha, ha, ha... the prices for even small drives it out of my budget  
right now.

Oh well, would have been nice to try a ZFS mirror for my data drive.



--  
Shannon Hendrix
shannon at widomaker.com