10-23-2008
There is no fixed determination for a swap/RAM ratio - generally you have a good handle on it. 2x -> 3x the size of RAM is reasonable to start with. What you show with 5+ GB is not out of that range. And your calculation seems to me to be alright. This is my opinion. Do you see very high swap utilization right now? Is there something to indicate a big performance problem?
A lot of documentation simply gives an estimate of what a single app requires with no additional load on the system other than app users.
What I see:
If this is a commercial application with more than 10 concurrent users, your system could be short on disk for a real db application. Example: we have a CIS with .5 terabytes of data and 450 users. It is installed across 20 filesystems each on physically distinct disks.
The point is there was a lot of load balancing needed early on to get things to work well, like keeping swap separate from tablespaces, putting active tablespaces on their own filesystem/disk. You cannot do much of that with 2 physical disks.
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LEARN ABOUT HPUX
vxbootsetup
vxbootsetup(1M) vxbootsetup(1M)
NAME
vxbootsetup - set up system boot information on a Veritas Volume Manager disk
SYNOPSIS
/etc/vx/bin/vxbootsetup [-g diskgroup] [medianame ... ]
DESCRIPTION
The vxbootsetup utility configures physical disks so that they can be used to boot the system. Before vxbootsetup is called to configure a
disk, the required volumes, standvol, rootvol and swapvol (and optionally, dumpvol) must be created on the disk. All of these volumes must
be contiguous with only one subdisk.
The -g option may be used to specify the boot disk group.
If no medianame arguments are specified, all disks that contain usable mirrors of the root, swap, /usr and /var volumes are configured to
be bootable.
If medianame arguments are given, only the disks that are associated with the specified disk names are configured to be bootable.
vxbootsetup requires that:
o The root volume must be named rootvol and must have a usage type of root.
o The swap volume must be named swapvol and must have a usage type of swap.
o The volumes containing /usr and /var (if any) must be named usr and var, respectively.
See the chapter "Recovery from Boot Disk Failure" in the Veritas Volume Manager Troubleshooting Guide for detailed information on how the
system boots and how VxVM impacts the system boot process. The vxmirror, vxrootmir, and vxresize utilities call vxbootsetup automatically.
If you use vxassist, or vxmake and vxplex to create mirrors of the root volume on a disk, you must run vxbootsetup explicitly to make the
disk bootable.
ARGUMENTS
medianame
Specifies the disk name (disk media name) of a VM disk that is to be configured as bootable.
SEE ALSO
disksetup(1M), edvtoc(1M), vxassist(1M), vxevac(1M), vxinstall(1M), vxintro(1M), vxmake(1M), vxmirror(1M), vxplex(1M), vxresize(1M),
vxrootmir(1M)
Veritas Volume Manager Troubleshooting Guide
VxVM 5.0.31.1 24 Mar 2008 vxbootsetup(1M)