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Re: Why did control channel closes itself?


Frank Ch. Eigler wrote:
> "Peter Teoh" <htmldeveloper@gmail.com> writes:
> 
>> [...]
>> stapio:stp_main_loop:282 nb=46
>> ERROR: probe overhead exceeded threshold

If you'd like to disable this threshold check error,
you can use -DSTP_NO_OVERLOAD option. (NOTE: it might cause system slowdown)

>> stapio:stp_main_loop:282 nb=53
>> WARNING: Number of errors: 1, skipped probes: 2
>> stapio:stp_main_loop:282 nb=51
>> WARNING: There were 45618 transport failures.
>> [...]
>> Notice the error "probe overhead exceeded threshold".   And
>> subsequent control-C does not stop the execution, it just hanged
>> without any response.
> 
> At this point, the script/module should already be unloading.  If
> there are thousands of kprobes, this can unfortunately take a long
> time (number-of-probes/CONFIG_HZ seconds),

It also depends on how many processors your system has.

> until we get the
> bulk-unregistration kprobe support code into the kernel.  (Masami,
> how is that bug #3542 going?)

Oh, it was fixed on the latest -mm tree (not yet merged to linus tree).

Thanks,

-- 
Masami Hiramatsu

Software Engineer
Hitachi Computer Products (America) Inc.
Software Solutions Division

e-mail: mhiramat@redhat.com


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