On Oct 12, 2009, at 10:45 AM, Thomas Backman wrote: >Here's the original thread (not from the beginning, though): >http://lists.freebsd.org/pipermail/freebsd-performance/2009-October/003843.html
>Long story short, my version: when the disk is stressed hard enough, >console IO becomes COMPLETELY unbearable. 10+ seconds to switch >between windows in screen(1), running (or even typing) simple >commands, etc. This happens both via SSH and the serial console. >How to reproduce/test: >1) time file /etc/* > /dev/null a few times, or something similar that >uses the disk; write down a common/average/median/whatever time. >2) cat /dev/zero > /uncompressed_fs/filename # please make *sure* it's >uncompressed, since ZFS with lzjb/gzip enabled will squish this into a >kilobyte-sized file, thus creating virtually *no* IO. >3) When cat has been running say 10 seconds, re-time command #1 and do >some interactive stuff - run commands, edit files, etc. Hi Thomas, I'm trying to reproduce the issue though I don't have any ZFS filesystems. I'm not using SSH neither serial console. My system is quite responsive. I'm using a VmWare system with 2 cpu support, 1MB RAM with FreeBSD 7.2-RELEASE. I don't know if the issue is related to ZFS or your hardware configuration but can you report what top(1) say during the slowdown? -- Giovanni Trematerra _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
