On 8/16/23 16:45, Nick Neumann wrote:
I've tried advocating for this via github issues a couple times (https://github.com/axboe/fio/issues/1544, https://github.com/axboe/fio/pull/1353/commits) but haven't had much luck/interest. I thought I'd try here and see if I could get enough interest to get some improvements to fio timekeeping committed. :-) The main issue is that by default, fio log files use timestamps based on an epoch that is the beginning of the job. If you have multiple jobs, especially with some jobs waiting on other jobs before starting, this means you have different epochs and the times in the logs for each job cannot be compared/ordered. Using log_alternate_epoch solves this problem since with it all logs share a common epoch, but introduces a different problem of not knowing the start time for each job relative to the common epoch. Using the default beginning of job epoch for log files, but also recording the start time of each job against a common (alternate) epoch, would solve both problems and bring other minor benefits too. Any thoughts? Issue 1544 has a 6-month-old PR that implements this. I'm happy to update, make changes, or approach it differently if desired. Thanks, Nick
I've left feedback at https://github.com/axboe/fio/pull/1353. I think we should be able to get something done to get this working for you.
Vincent
