Can someone quickly review the partition plan below for dual booting Kubuntu and OracleLinux? Any suggestions highly appreciated.

Many thanks for your time and attention.

/dev/sda (225GB)
+-/dev/sda1 /boot (500MB, ext2) Kubuntu11.10
+-/dev/sda2 data (100GB, ext4) Shared (non OS files)
+-/dev/sda3 swap (3GB, ext3) Shared
+-/dev/sda4 extended (120GB, ext4)
+-/dev/sda5 /tmp (2GB, ext4) Kubuntu11.10
+-/dev/sda6 /home (15GB, ext4) Kubuntu11.10
+-/dev/sda7 / (20GB, ext4) Kubuntu 11.10
+-/dev/sda8 /boot (500MB, ext4) OEL6.2
+-/dev/sda9 /tmp (2GB, ext4) OEL6.2
+-/dev/sda10 /home (10GB, ext4) OEL6.2
+-/dev/sda11 / (15GB, ext4) OEL6.2
+-/dev/sda12 /oracle (20GB, ext4) Oracle11gR2 + datafiles + tools
Free Space = 15GB

Probably more swap than you really need. Swap is formatted as swap, not ext3. I share /boot with all my distros by putting a subdirectory for each distros' kernels under /boot. I also share /home amongst my three distros. Something to think about unless you don't mind keeping two sets of configuration files (e.g., xinitrc, bash_profile, bashrc, etc.).

Similar to above. I have a 60GB hard drive, dual booting OpenSuSE 12.1 with Gnome & SlackWare 13.37 with Xfce
My partition went like

10GB Root for OpenSuse
10GB Root for SlackWare
2 GB Swap for both of them (Shared)
38GB Home (Documents, Downloads, Music, Pictures, Videos) for both of them

I was advice not to use the same user name for both of them so I named my user like John for OpenSuSE and John1 for Slackware.

I was also advice no to use the same version of Desktop Environment. And I am using GRUB to boot them.

I like this set up but I wish my hard drive had more room for more stuff.

Good luck to you!

Thank you very much friends.

The discussion with one of my friends lead me to reconsider unnecessary partitioning and here is my new plan:

1 primary partition for Kubuntu (20 GB)
1 primary partition for OL 6.2 (20 GB)
1 primary partition for swap Kubuntu/OL 6.2 ( 5 GB )
1 extended partition (ext3) for Oracle db files and FRA (30 GB)
1 extended partition for a shared disk (100 GB) DATA (non OS)
50GB free

No /boot and /tmp partitions.

The only thing is I already have 100GB "data" partition (non OS files) as a primary partition that is 75% filled up. So I am planning to create SWAP inside extended partition instead of as a primary so I will have 3 primary + 1 extended. Or may be during installation of first OS (Kubuntu) I will boot into LiveCD mode and try to move "data" partition into extended and delete the primary one later. Not sure if that can be done, else will go as mentioned above (SWAP inside extended).

I just want to make sure I am on a right path before proceeding hence asking for opinions from the experts that played a lot with these things

Thanks again for your attention.