Jens, sync IO: You're right, this should work. The code change simply adds the check for numberio to the existing fio infrastructure. I think my first attempt had some problems and I did not test asynchronous io on my finished code. I will run some tests to make sure that it works with asynchronous io. equal size read/writes: I just realized after running a quick test that there is a problem. With different read/write sizes, fio exited with an error: fio: verify.c:960: populate_hdr: Assertion '0' failed. I think this has to do with the offsets of the read and write blocks being different when they're of different sizes. I need to figure out what is going on. Any ideas Jens? Here is the job used: readwrite=randrw randrepeat=1 size=1m bs=4k,8k ioengine=libaio direct=1 buffered=0 rwmixread=30 rwmixwrite=70 norandommap loops=2 verify=meta verify_pattern=0xffffffffffffffff verify_dump=1 continue_on_error=verify On Tue, Aug 27, 2013 at 10:22 AM, Grant Grundler <grundler@xxxxxxxxxxxx> wrote: > On Tue, Aug 27, 2013 at 10:02 AM, Jens Axboe <axboe@xxxxxxxxx> wrote: > ... >>> +data_integrity_check >>> + If this option is given, fio will check the i/o number of >>> + each block read back during the verification phase. Fio >>> + checks numberio to detect stale blocks. Currently, this >>> + option requires synchronous i/o, and equal-sized read and >>> + write blocks. This option requires workloads that write data. >> >> I think this use case is just too narrow. > > Jens. > This behavior should be standard behavior for the data integrity > checking. To debug data corruption problems we need to know if it's > stale data or corrupted data. Huge difference in how to track it down > and potential causes. I'm arguing it shouldn't even be an option. > >> Why does it require sync IO and equal read/write sizes? >> Can't you just replay and re-generate and compare? > > I think it's just limitations of this implementation and testing. In > principle I think you are right. Perhaps Juan can explain in more > detail. > > cheers, > grant -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
