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Diffstat (limited to 'Documentation/filesystems/proc.txt')
| -rw-r--r-- | Documentation/filesystems/proc.txt | 37 |
1 files changed, 33 insertions, 4 deletions
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 4a37e25e694..dec99455321 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -347,7 +347,35 @@ connects the CPUs in a SMP system. This means that an error has been detected, the IO-APIC automatically retry the transmission, so it should not be a big problem, but you should read the SMP-FAQ. -In this context it could be interesting to note the new irq directory in 2.4. +In 2.6.2* /proc/interrupts was expanded again. This time the goal was for +/proc/interrupts to display every IRQ vector in use by the system, not +just those considered 'most important'. The new vectors are: + + THR -- interrupt raised when a machine check threshold counter + (typically counting ECC corrected errors of memory or cache) exceeds + a configurable threshold. Only available on some systems. + + TRM -- a thermal event interrupt occurs when a temperature threshold + has been exceeded for the CPU. This interrupt may also be generated + when the temperature drops back to normal. + + SPU -- a spurious interrupt is some interrupt that was raised then lowered + by some IO device before it could be fully processed by the APIC. Hence + the APIC sees the interrupt but does not know what device it came from. + For this case the APIC will generate the interrupt with a IRQ vector + of 0xff. This might also be generated by chipset bugs. + + RES, CAL, TLB -- rescheduling, call and TLB flush interrupts are + sent from one CPU to another per the needs of the OS. Typically, + their statistics are used by kernel developers and interested users to + determine the occurance of interrupt of the given type. + +The above IRQ vectors are displayed only when relevent. For example, +the threshold vector does not exist on x86_64 platforms. Others are +suppressed when the system is a uniprocessor. As of this writing, only +i386 and x86_64 platforms support the new IRQ vector displays. + +Of some interest is the introduction of the /proc/irq directory to 2.4. It could be used to set IRQ to CPU affinity, this means that you can "hook" an IRQ to only one CPU, or to exclude a CPU of handling IRQs. The contents of the irq subdir is one subdir for each IRQ, and one file; prof_cpu_mask @@ -785,9 +813,9 @@ Various pieces of information about kernel activity are available in the since the system first booted. For a quick look, simply cat the file: > cat /proc/stat - cpu 2255 34 2290 22625563 6290 127 456 - cpu0 1132 34 1441 11311718 3675 127 438 - cpu1 1123 0 849 11313845 2614 0 18 + cpu 2255 34 2290 22625563 6290 127 456 0 + cpu0 1132 34 1441 11311718 3675 127 438 0 + cpu1 1123 0 849 11313845 2614 0 18 0 intr 114930548 113199788 3 0 5 263 0 4 [... lots more numbers ...] ctxt 1990473 btime 1062191376 @@ -807,6 +835,7 @@ second). The meanings of the columns are as follows, from left to right: - iowait: waiting for I/O to complete - irq: servicing interrupts - softirq: servicing softirqs +- steal: involuntary wait The "intr" line gives counts of interrupts serviced since boot time, for each of the possible system interrupts. The first column is the total of all |