The parameters:
>> maxfiles 512 1024
This value is a soft value for users and can be changed using ulimit in the standard POSIX shell, but it has no effect on the kernel since it is simply a fence or limit to the number of files that can be opened by a single process.
>> dbc_pct_max 50% 10%
This is a good change. 10% for a 2Gb RAM system is 200 megs, about right for the buffer cache. However, running Oracle and SAP in 2Gb is strangling the applications! You need a minimum of 4Gb and ideally 6-8Gb for reasonable performance.
shmmax 2147483648 3221225472
For a 64bit application, this is fine and like maxfiles, has no effect on the kernel as it is a fence for the maximum shared memory size that can be obtained. For 32bit applications, it is meaningless since the maximum value allowed is 960megs (or 1750 megs for shared MAGIC executables). These 32bit executables are allowed to use an additional quadrant for shared memory--but that shared memory is part of a single shared memory area that ALL 32 bit applications must share.
>> maxtsiz_64bit 1073741824 2147483648
Do you really have an executable file that is 2000 megs in size? maxtsiz is the text or non-data area of the program and is fairly close to the size of the executable file itself. Most programs are just a few megs in size unless they have millions of lines of code. Like maxfiles and shmmax, this has no effect on the kernel as it is simply a fence. You can change it back or leave it as is.
>> maxdsiz_64bit 17179869184 2147483648
Another fence value. Was the original value actually 17Gb? This is no problem for a 64bit program but if usewd by a 64bit program, could cripple the tiny RAM you have in this machine. The new 2Gb value is more reasonable BUT I would add another 3-6Gb of temporary swap space to see if things start working. If so, processes will run extremely slowly since pageouts will be very high (indicating that you need a lot more RAM).
Oracle and SAP need enormous amounts of virtual memory for installation (8 to 10Gb). Since HP-UX is a virtual memory system, you can run 10 Gb of processes in 2Gb of RAM but you'll need at least 8Gb of swap space, 12Gb of swap space if you have swapmem_on=0. Swapping (paging) is a very bad thing for performance, but if you have lots of time on your hands and no money for RAM, then swapping is your only choice. Note that Oracle and SAP do NOT need dozens of Gb of swap space after they are loaded. The vendor docs fail to mention this and can be verified by running: swapinfo -tam
Be sure to get a copy of shminfo (as mentioned in many previous posts to the ITRC):
ftp://contrib:9unsupp8@hprc.external.hp.com/sysadmin/programs/shminfo/
Also mentioned is that ftp:\\ has a big bug in many version of IE (no problems in Netscape or Opera or lynx). Turn OFF folder view in IE using the Advanced options in Tools->Internet.
Bill Hassell, sysadmin
