Red Hat Bugzilla – Bug 116733
kernel hangs or crashes when hugetbl is on and Oracle 10g uses it
Last modified: 2007-11-30 17:07:00 EST
Description of problem:
On a system with 20GB ram running the RHEL3 hugemem kernel
and hugetbl_max set to 8192 (which strangely enough
/proc/meminfo reports as being just 4096 pages, and it
looks like meminfo is right) when I run Oracle 10g using
lots of memory the kernel suddenly panics or just simply
Version-Release number of selected component (if applicable):
Happens every other time I start Oracle (with a configuration
that really uses lots of memory)
Steps to Reproduce:
1. Install Oracle 10g
2. modify oracle to lower-mapped-base specs (optional)
3. modify oracle to enable aio (optional)
4. echo 8192 > /proc/sys/kern/hugetbl_max
5. specify sga_max_size = 3500M
6. specify db_buffer_cache = 2000M
--> of course I don't expect you to do all this, just to
debug a kernel error. I would make a program that
actually allocates lots of hugetbl shared memory
and uses it heavily.
system runs happily :-)
Please include information about the hardware being used, as well as
information about whether or not it happens on multiple machines.
Hardware is a ProLiant DL780 (?) or so, it's got 4 CPUs.
I can't tell whether it happens on multiple machines. What
I do know is that when it actually panics and I get to
see the dump output, it does mumble something about hugetbl
Can you please get several "AltSysrq M" outputs when the system is
hung while running 10g with hugltlb pages? I cant reproduce this
Thanks, Larry Woodman
Please try to reproduce this problem with the latest RHEL3-U2 kernel
(2.4.21-14.EL). We found and fixed a problem which sounds exactly
like this one in that kernel.
Gunther, whats the status of this bug? I havent seen any update in
the last 3 months.
Closing due to lack of activity. If there is additional information, please
reopen and provide the information.