Dear all, First, I would like to thank you all for your efforts. I have been trying to use blkparse/blktrace to trace io activity for my research. I want to to measure IO response time to better characterize linux io. My problem is that I am trying to use blkparse to get the request response time for some activity. I gave the -t switch along with %u to print it out. While it does work for some requests. It gives "Expecting elapsed value" and bails out. When I turn on verbose output, it also generates "complete not found for XXYYZZ" when I request verbose results. >From what I gather. Some blocks return completion twice for synchronous writes. But it can also happens for reads. I am attaching an annotated excerpt from the results. In these results I have intentionally disabled the bailout accompanying "Expecting elapsed value" so blkparse would not exit. For a trace that has ~1.4M requests, I have seen this error 90K times. The arguments are: ./blkparse -v -t -F C,"COMP %D %2c %8s %16S %5T.%9t %5p %2a %3d %3u\n" -F D,"ISSUED %D %2c %8s %16S %5T.%9t %5p %2a %3d\n" -i ./results/sda.blktrace. NOTE: This still happens well into the tracing process. E.g. Multiple hours into the tracing process. But you should have commented the exit(1) after fprintf(stderr, "Expecting elapsed value\n"); Otherwise, it will bail out at the first occurance. Any help will be greatly appreciated. Regards, -Tarihi
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