11.2-STABLE kernel wired memory leak

Eugene Grosbein eugen at grosbein.net
Tue Feb 12 18:40:24 UTC 2019

13.02.2019 1:18, Mark Johnston wrote:

> On Wed, Feb 13, 2019 at 01:03:37AM +0700, Eugene Grosbein wrote:
>> 12.02.2019 23:34, Mark Johnston wrote:
>>> I suspect that the "leaked" memory is simply being used to cache UMA
>>> items.  Note that the values in the FREE column of vmstat -z output are
>>> quite large.  The cached items are reclaimed only when the page daemon
>>> wakes up to reclaim memory; if there are no memory shortages, large
>>> amounts of memory may accumulate in UMA caches.  In this case, the sum
>>> of the product of columns 2 and 5 gives a total of roughly 4GB cached.
>>>> as well as "sysctl hw": http://www.grosbein.net/freebsd/leak/sysctl-hw.txt
>>>> and "sysctl vm": http://www.grosbein.net/freebsd/leak/sysctl-vm.txt
>> It seems page daemon is broken somehow as it did not reclaim several gigs of wired memory
>> despite of long period of vm thrashing:
> Depending on the system's workload, it is possible for the caches to
> grow quite quickly after a reclaim.  If you are able to run kgdb on the
> kernel, you can find the time of the last reclaim by comparing the
> values of lowmem_uptime and time_uptime.

Yes, I have debugger compiled into running kernel and have console access.
What commands should I use?

More information about the freebsd-stable mailing list