On 09/28/2018 09:37 PM, Dave Ulrick wrote: > Note: I don't think this is an issue with buffered I/O to stdout per se. I > say this because I'm seeing pretty consistent run times if I write to stdout > _as long as the output file didn't previously exist_. Rather, the issue seems > to be with _overwriting_ an existing disk file when I/O redirection is used.
Try to add a "sync" before each test to really exclude a buffered I/O influence. Your measurements show a 100% CPU in the fast test and lower CPU usage for the slow cases, so I would still bet on buffering effects (has the previous outfile been flushed to disk?). You have not even specified which filesystem you are using and which storage hardware (HD or SSD?). Regards. -- Roberto Ragusa mail at robertoragusa.it _______________________________________________ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://getfedora.org/code-of-conduct.html List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org
