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[[!tag open_issue_gnumach]]
IRC, unknown channel, unknown date:
`cat < /dev/zero | cat > /dev/null` will eventually make the system crash,
likewise when using a FIFO.
<antrik> hm... VM activity seems much higher when running fifo than pfinet... may be the cause
<antrik> "zero filled" and "page faults" are serveral times higher with pipe than with pfinet
<antrik> (cow faults however are about the same...)
<antrik> pflocal is about the same as fifo
<antrik> no, because it usually takes like 20 minutes until it crashes, sometimes much longer
<antrik> not sure, but the longest so far was in the range of hours IIRC
<antrik> I think I never tested what happens on "cat /dev/zero >/dev/null"... another thing yet to try
<antrik> Linux BTW seems to employ some major VM trickery in this case -- dd shows a transfer rate of 10 GB/s...
<antrik> no, no anomalies in vmstat
<antrik> the only observation I made is that number of page faults and some other number rise pretty quickly with pflocal and fifo, but not with pfinet
<antrik> I guess that's somehow related to the fact that pfinet doesn't crash -- though I guess the difference is simply that pfinet is way slower...
<antrik> (haven't checked that, though)
<antrik> BTW, I'm not sure you got it right: the test case is "cat /dev/zero|cat >/dev/null", *not* "cat /dev/zero >/dev/null"
<antrik> OK, "cat /dev/zero|tail -c 1" also crashes, so it's definitely not related to /dev/null
<antrik> "dd if=/dev/zero|tail -c 1" crashes as well
<antrik> but "tail -c 1 /dev/zero" doesn't seem to
<antrik> cool... running multiple instances of the pipe test also considerably speeds up the crash
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