11.2-STABLE kernel wired memory leak

Eugene Grosbein eugen at grosbein.net
Tue Feb 12 18:03:56 UTC 2019

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:

$ sed 's/:/,/' vmstat-z.txt | awk -F, '{printf "%10s %s\n", $2*$5/1024/1024, $1}' | sort -k1,1 -rn | head
      1892 abd_chunk
   454.629 dnode_t
    351.35 zio_buf_512
   228.391 zio_buf_16384
   173.968 dmu_buf_impl_t
    130.25 zio_data_buf_131072
   93.6887 VNODE
   81.6978 arc_buf_hdr_t_full
   74.9368 256
   57.4102 4096

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