Where to put my swap

[Gary Cooper_1]

Don't laugh... I have a D270 with 256Mb RAM. It has 2 internal 4Gb and 1 external 2Gb disks. (I've been reading other posts on swap where users talk about 8Gb RAM, so I've got a bit of an inferiority complex now!)

I am just in the process of upgrading it from HP-UX 10.20 to HP-UX 11.11. It is used as a host for my users home directories which are NFS mounted to the other machines on the network and also a primary DNS/NIS server. ( I have a small network of around a dozen users, no connection to 'the outside world').

Clearly my root disk will be an internal 4Gb disk; I want to use the other 4Gb disk for /home. that leaves me with the external 2Gb disk...

My thought's are to put /tmp and swap on it. Whilst I know I can put swap on it, do I also have to have some in vg00? or can I put it all on the 2Gb disk (4Gb is a bit tight for the root disk, hence wanting to move /tmp & swap off it completely).

Any other suggestions as to where to put the various file systems would be welcome.

BTW, I was going to size the swap at 512Mb - my current (temporary) home/DNS/NIS server seems to be using around 200Mb.

Thanks,

Gary Cooper

[Karthik S S · Accepted solution]

I would suggest you to club both the 2GB and 4Gb HDDs to VG00 during the installation. This leaves you more room for planning for SWAP. 512MB of swap shpuld be sufficient.

-Karthik S S

[Mark Grant]

Yes, you have to have some swap on vg00 because when the machine is booting none of the other volume groups are activated yet as is the case when you are in single user mode. You don't need masses of it in there though, just enough to keep going until your other volume groups are activated.

[Robert-Jan Goossens]

Hi Gary,

/dev/vg00/lvol3 250 mb /
/dev/vg00/lvol1 100 mb /stand
/dev/vg00/lvol7 650 mb /var
/dev/vg00/lvol6 700 mb /usr
/dev/vg00/lvol5 250 mb /tmp
/dev/vg00/lvol4 1000 mb /opt

/dev/vg00/lvol2 600 mb

swap 2,5 X internal mem

Above is my configuration for a small sized server, you could move some mb's from opt to var and usr in yours. the 4 GB should be enough for your OS plus swap.

Hope this helps a bit,
Kind regards,
Robert-Jan

[Gary Cooper_1]

Hi Guys,

Thanks Mark - that was exactly the information I needed.

Possible at the risk of getting sidetracked here, but...

Would it be better to bundle the 4+2Gb disks into one volume group? That way, /var (e.g.) could be on both disks. What are the performance implications of doing this rather than putting the 2Gb disk in a separate VG?

The other thing is Robert-Jan's figures for a small server. I have a D250 which is currently doing what my D270 is going to do. All it's got on it is HP-UX 11.11, pretty much straight out of the box, no third-party applications. It is currently using

Filesystem kbytes used avail %used Mounted on
/dev/vg00/lvol3 143360 84680 58272 59% /
/dev/vg00/lvol1 295024 44480 221040 17% /stand
/dev/vg00/lvol8 524288 426840 97288 81% /var
/dev/vg00/lvol7 1433600 1078728 352160 75% /usr
/dev/vg00/lvol6 262144 11288 248960 4% /tmp
/dev/vg00/lvol5 2097152 1443592 648504 69% /opt
/dev/vg01/lvol1 4186112 2051669 2009481 51% /home

I.e. your figures for /opt & /usr are certainly too low, but the interesting one is /standâ ¦ in fact, itâ s interesting on two counts. Firstly the bdf output figures donâ t add up â thereâ s about 30Mb missing! The other thing is that the HP-UX installation seems to offer a default size of 300Mb. This seems to be way overkill. None of my machines (11 in all) use more than about 57Mb of /stand.

[Robert-Jan Goossens]

Hi, sorry for the confusion. For the upgrade to 11.i you will need more space in /usr. /opt depends on what you got installed on the server. I use /app (vg01) for applications like oracle etc.

/stand is a hfs filesystems use about 10 percent overhead, this normal behavior.

Using the 2 GB disk in your vg00 is an option, and yes you could use /var on both disks. If you only install OS data in vg00 I don't think you will loose performance.

Hope this helps,
Robert-Jan

[Trond Haugen]

If you havent already done so you should also take a look at the "HP-UX 11i Installation and Update Guide" at docs.hp.com
http://docs.hp.com/hpux/os/11i/index.html#Installing%20and%20Updating

Regards,
Trond

[Pete Randall]

Gary,

To me, with a system of minimal size like this, I would be tempted to put everything into vg00. That way you'll have maximum flexibility in sizing filesystems and swap space, yet you're not introducing any "non-root" data other than /home.

I also think you're going to be very lucky to get anywhere near acceptable performance out of this system with only 256MB RAM. You might want to start pricing memory upgrades. Perhaps on the used market to save some money?


Pete

[Gary Cooper_1]

OK, thanks guys.

I think I'm going to to as you suggest and combine the 2Gb & 4Gb disks into vg00.

Thanks again,

Gary

[Gary Cooper_1]

BTW,

We've been running this machine for the same purpose for a few years now with 10.20 and the performance was OK.

The machine is getting a bit long in the tooth and I suspect we'll replace it in the not too distant future (certainly if any of the hardware goes end-of-life).

Thanks again,

Gary