Messages in this thread | | | Date | 26 Feb 2001 01:21:12 -0000 | From | "Rico Tudor" <> | Subject | 64GB option broken in 2.4.2 |
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Subject: 64GB option broken in 2.4.2
Problem: The 64GB option causes processes to spin in the kernel.
Setup: Linux 2.4.2 Slack current 20-feb-2001 ServerWorks III HE 4GB main memory dual 933 Piii: SL47Q (stepping 3), SL4KK (stepping 6) gcc 2.95.2 19991024 (release)
Test procedure: On /dev/tty1, type
cat /dev/sda >/dev/null # or any fast disk
On /dev/tty2, type
while sleep 0; do date; done
On /dev/tty3, type
top
The purpose of the disk read is to provide some nondeterminism, which triggers the bug. `top' lets you watch the debacle.
Observation: After a short time, dates will appear with increasing irregularity. `top' will show `sleep' and `date' processes racking up many seconds of CPU time. At this point, terminate the disk read, and one of these processes will go completely CPU-bound, and uninterruptible. In this state, the system is unusable, since any exec'd process has a good chance of being bushwhacked in the kernel.
Variations: noapic problem remains mem=1200m problem remains nosmp noapic problem fixed mem=800m problem fixed 4GB option problem fixed
Hypothesis: Code to handle PAE has buggy spinlock management. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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