Messages in this thread | | | Subject | Re: [2.5.70] possible problem with /dev/diskstats | Date | Sun, 01 Jun 2003 12:05:07 -0700 | From | Rick Lindsley <> |
| |
Documentation/iostats.txt says about diskstats: [SNIP] Field 9 -- # of I/Os currently in progress The only field that should go to zero. Incremented as requests are given to appropriate request_queue_t and decremented as they finish. [SNIP]
But here is a cat /proc/diskstats: 3 0 hda 948 317 16216 4294408142 90 333 848 7309 4294967294 7309215 4280372198 ~~~~~~~~~~
Yes, I've had a couple of other reports of this. I suspect there is a path by which an "I/O" appears to have been completed while none was begun. I've only noticed this on my hda drive as well. What I didn't notice was exactly when this behavior began, which may have been useful in tracking down the problem. You'll notice a couple of other values there in the 4.2 billion range that probably suffer from a similar (or maybe the same) issue. I haven't seen this on SCSI drives yet, just hda drives, which suggests there may be something about that I/O path that bears some closer scrutiny.
Rick - 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/
| |