FreeBSD & Software RAID

[Adam Vande More]

Sweet thanks for the info.  Building one of those boxes is next in the list.

On 5/26/09, Steve Bertrand <steve at ibctech.ca> wrote:
> Howard Jones wrote:
>> Wojciech Puchar wrote:
>>> you are right. you can't be happy of warm house without getting really
>>> cold some time :)
>>>
>>> that's why it's excellent that ZFS (and few other things) is included
>>> in FreeBSD but it's COMPLETELY optional.
>>>
>> Well, I switched from the heater that doesn't work and is poorly
>> documented (gvinum) to the one that does and  is (zfs, albeit mostly
>> documented by Sun), and so far I am warm :-)
>>
>> Once I'd increased kmem, at least. I did get a panic before that, but
>> now I am shuffling data happily and slightly faster than gvinum did, and
>> memory has levelled off at about 160MB for zfs. I'll be keeping my
>> previous hardware RAID in one piece for a little while though, I think,
>> just in case! (old Adaptec card with a 2TB limit on containers).
>
> I moved my AMANDA tapeless backup system to ZFS well over a year ago.
> It's got four 500GB SATA drives.
>
> At first, it would panic frequently sometime during the backup. The
> backups peak at ~400Mbps of network traffic. I adopted the following
> script to write out the memory usage during the backup, so I could
> better tune the system (sorry, I can't recall where I found this code snip):
>
> #!/bin/sh
>
> TEXT=`/sbin/kldstat | /usr/bin/awk 'BEGIN {print "16i 0";} NR>1 \
> {print toupper($4) "+"} END {print "p"}' | dc`
>
> DATA=`/usr/bin/vmstat -m | sed -Ee \
> '1s/.*/0/;s/.* ([0-9]+)K.*/\1+/;$s/$/1024*p/' | dc`
>
> TOTAL=$((DATA + TEXT))
> DATE=`/bin/date | awk '{print $4}'`
>
> /bin/echo $DATE `/bin/echo $TOTAL | \
> /usr/bin/awk '{print $1/1048576}'` >> /home/steve/mem.usage
>
> Cronned every minute, I'd end up with a file like this:
>
> 19:16:01 500.205
> 19:17:02 485.699
> 19:18:01 474.305
> 19:19:01 473.265
> 19:20:01 471.874
> 19:21:02 471.94
>
> ...the next day, I'd be able to review this file to see what the memory
>  usage was at the time of the panic/reboot.
>
> I found that:
>
> vm.kmem_size="1536M"
> vm.kmem_size_max="1536M"
>
> made the system extremely stable, and since then:
>
> amanda# uptime
>  9:01AM  up 81 days, 17:06,
>
> I'm about to upgrade the system to -STABLE today...
>
> Steve
>


-- 
Adam Vande More
Systems Administrator
Mobility Sales