Messages in this thread | | | Date | Sat, 28 Jun 2008 19:44:14 -0700 | From | Jeremy Fitzhardinge <> | Subject | Re: Ctrl+C doesn't interrupt process waiting for I/O |
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Török Edwin wrote: > Hi, > > I have encountered the following situation several times, but I've been > unable to come up with a way to reproduce this until now: > - some process is keeping the disk busy (some cron job for example: > updatedb, chkrootkit, ...) > - other processes that want to do I/O have to wait (this is normal) > - I have a (I/O bound) process running in my terminal, and I want to > interrupt it with Ctrl+C > - I type Ctrl+C several times, and the process is not interrupted for > several seconds (10-30 secs) > - if I type Ctrl+Z, and use kill %1 the process dies faster than > waiting for it to react to Ctrl+C > > This issue occurs both on my x86-64 machine that uses reiserfs, and on > my x86 machine that uses XFS, so it doesn't seem related to the > underlying FS. > I use 2.6.25-2 and 2.6.26-rc8 now; I don't recall seeing this behaviour > with old kernels (IIRC I see this since 2.6.21 or 2.6.23). > > Is this intended behaviour, or should I report a bug? >
Yes, it's intended behaviour. Filesystem IO syscalls are considered "fast" and are interruptible. Usermode code can reasonably expect that file IO will never return EINTR.
That said, if a program is blocking for tens of seconds in block IO, then that could be a problem in itself.
J -- 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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