Memory in Database server (OE 10.2B)

[rguerrer]

Hi everyone,

I hope someone can help with this: I migrate a Database Server from Solaris SPARC to SUSE Linux (OE 10.2b Enterprise 32-bits). But i realize that when i was use solaris the memory (RAM) was used and release. But now in linux i can see when start database and users start to connect, the memory used is almost 100%, but never release it, althoug users disconnect.

Is there some parameter special to manage memory in linux? for the kernel or for database?

top - 16:59:32 up 2 days, 4:48, 8 users, load average: 0.78, 0.39, 0.24
Tasks: 380 total, 4 running, 376 sleeping, 0 stopped, 0 zombie
Cpu(s): 8.0%us, 0.6%sy, 0.0%ni, 91.4%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%
Mem: 48260M total, 48023M used, 237M free, 708M buffers
Swap: 40962M total, 11M used, 40951M free, 46288M cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
10096 root 20 0 1238m 1.2g 1.2g R 99 2.5 11:02.86 _mprosrv
10186 root 20 0 1235m 687m 687m R 12 1.4 8:09.40 _mprosrv
10304 root 20 0 1238m 1.1g 1.1g S 9 2.4 10:09.84 _mprosrv
10243 root 20 0 1235m 977m 977m S 6 2.0 13:05.65 _mprosrv

 

[Rob Fitzpatrick]

You should expect to see virtually all of your memory "used" when you look at top. Any memory that is not in use by processes will be taken by the OS for use as file system cache. And given back when processes want to allocate memory.

I think a better question for you to be asking yourself is, "Why am I severely limiting my database buffer pool size by using a 32-bit RDBMS?"