Re: wired memory leak at r298785

> On May 3, 2016, at 12:20 AM, Mark Johnston <markj_at_FreeBSD.org> wrote:
> 
> On Mon, May 02, 2016 at 08:55:58PM -0400, Steve Wills wrote:
>> Hi,
>> 
>> On 05/ 2/16 09:32 AM, Steve Wills wrote:
>>> Hi,
>>> 
>>> Just did my monthly update and r298785 seems to be leaking wired memory
>>> rather rapidly. My system has 8gb of RAM and the amount of wired memory
>>> just goes up and up continuously. It takes about 12 hours before it
>>> exhausts all the RAM and sort of locks up (though shutdown still works).
>>> 
>>> I also made one other change to the system at the same time as updating,
>>> which was to add another disk and configure it using ZFS. Perhaps this
>>> is a ZFS on PowerPC64 issue? My amd64 box running the same rev of
>>> CURRENT doesn't have the issue.
>>> 
>> 
>> I've rebooted the box and started repeatedly logging the output of
>> vmstat -m. It seems to show CAM CCB using a lot of memory and growing
>> rather rapidly. For example, here's a few lines of diff output:
>> 
>> - CAM CCB 91418 182836K - 187149 2048
>> + CAM CCB 447070 894140K - 900292 2048
>> 
>> from two samples that are 60 minutes apart.
>> 
>> The box is isn't terribly busy, it's just running the monitoring daemons
>> running (snmpd, collectd), whatever web requests are hitting it (very
>> few if any), this logging process, and my shell, etc.
> 
> This was causing problems on one of my amd64 systems, so it's not
> specific to powerpc64. It turns out to be due to r298004: the CCB
> allocated in cam_periph_devctl_notify() never gets freed. The patch
> below seems to fix it.

Thanks Mark, that looks like the right fix.  I’ll put it in today.

Scott