time issues and ZFS

2013-01-21 Thread Daniel Braniss
After many trials (and errors), here are some facts: host: DELL PowerEdge R710, 16GB, mfi0: Dell PERC H700 Integrated mfid0: 14305280MB (29297213440 sectors) RAID volume 'r5' is optimal mfi1: Dell PERC 6 mfid1: 12393472MB (25381830656 sectors) RAID volume 'Virtual Disk 0' is optimal we

Re: time issues and ZFS

2013-01-21 Thread Adrian Chadd
Hi, Try experimenting with kern.eventtimer.periodic and kern.eventtimer.idletick. If this fixes it for you, please file a PR with all the relevant details. Thanks! Adrian On 21 January 2013 03:33, Daniel Braniss da...@cs.huji.ac.il wrote: After many trials (and errors), here are some

Re: time issues and ZFS

2013-01-21 Thread Daniel Braniss
Hi, Try experimenting with kern.eventtimer.periodic and kern.eventtimer.idletick. can you give/point to some info about this? btw, I just noticed that on this hardware I get: 9.1-STABLE: vmstat -i interrupt total rate irq3: uart1 931

Re: time issues and ZFS

2013-01-21 Thread Ian Lepore
On Mon, 2013-01-21 at 13:33 +0200, Daniel Braniss wrote: After many trials (and errors), here are some facts: host: DELL PowerEdge R710, 16GB, mfi0: Dell PERC H700 Integrated mfid0: 14305280MB (29297213440 sectors) RAID volume 'r5' is optimal mfi1: Dell PERC 6 mfid1: 12393472MB

Re: time issues and ZFS

2013-01-21 Thread Daniel Braniss
... What's the output of sysctl kern.eventtimer? kern.eventtimer.periodic is 0 Does the bad behavior change if you set kern.eventimer.periodic=1? setting kern.eventtimer.timer=LAPIC instead of the default HPET made the missing cpu timers to

Re: time issues and ZFS

2013-01-21 Thread Ian Lepore
On Mon, 2013-01-21 at 17:35 +0200, Daniel Braniss wrote: ... What's the output of sysctl kern.eventtimer? kern.eventtimer.periodic is 0 Does the bad behavior change if you set kern.eventimer.periodic=1? setting

Re: time issues and ZFS

2013-01-21 Thread Adrian Chadd
I still firmly believe the ACPI event timer code is racy, and what we may be seeing here is the fallout from that. It's very possible that we're missing interrupts here - the new eventtimer code that made it into 9.x puts the halt behind a critical section, with interrupts disabled. The only

Re: time issues and ZFS

2013-01-21 Thread Daniel Braniss
I still firmly believe the ACPI event timer code is racy, and what we may be seeing here is the fallout from that. It's very possible that we're missing interrupts here - the new eventtimer code that made it into 9.x puts the halt behind a critical section, with interrupts disabled. The