OOM-killer and strange RSS value in 3.9-rc7

Han Pingtian
2013-04-16T11:00:24Z

Hi list,

On a power7 system, we have installed 3.9-rc7 and crash 6.1.6. If I run
something like "make -j 64" to compile linux kernel from source, sooner
or latter, oom-killer will be triggered. Before that, when I trying to
analyse the live system with crash, some processes' %MEM and RSS looks
too big:

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This GDB was configured as "powerpc64-unknown-linux-gnu"...

crash: read error: kernel virtual address: c00000000074ee38 type: "cpu_possible_mask"

crash: this kernel may be configured with CONFIG_STRICT_DEVMEM, which
renders /dev/mem unusable as a live memory source.

crash: trying /proc/kcore as an alternative to /dev/mem

KERNEL: /boot/vmlinux-3.9.0-rc7
DUMPFILE: /proc/kcore
CPUS: 80
DATE: Tue Apr 16 05:51:11 2013
UPTIME: 00:44:42
LOAD AVERAGE: 0.15, 0.53, 3.43
TASKS: 876
NODENAME: riblp3.upt.austin.ibm.com
RELEASE: 3.9.0-rc7
VERSION: #1 SMP Tue Apr 16 03:14:32 CDT 2013
MACHINE: ppc64 (unknown Mhz)
MEMORY: 4 GB
PID: 9086
COMMAND: "crash"
TASK: c0000000c3640000 [THREAD_INFO: c0000000d7900000]
CPU: 52
STATE: TASK_RUNNING (ACTIVE)

crash> ps -u rpc.idmapd
PID PPID CPU TASK ST %MEM VSZ RSS COMM
1823 1 1 c0000000a66c0000 IN 281474976710656.0 5312 18014398509480192 rpc.idmapd
crash>

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I'd like to ask if this a problem of the kernel or crash.

Thanks in advance.