Re: Unexpected out of memory kills when running parallel find instances over millions of files

[mlelstv%serpens.de@localhost (Michael van Elst)]

mjguzik%gmail.com@localhost (Mateusz Guzik) writes:

>> While vnodes would be recyclable, they hardly get recycled unless
>> an filesystem object is deleted or the filesystem is unmounted.

>They get recycled all the time by vdrain thread if numvnodes goes above
>desiredvnodes, like it does in this test.

They should also be recycled when memory gets tight but they aren't.

As a consequence, not only the vnodes stay in memory, but also all
cached pages (the UVM objects).


>> Without swap, the kernel also has no chance to evict process pages
>> to grow the vnode cache further.

>It should not be trying to grow the vnode cache. If anything it should
>stop it from blowing out of proportion and definitely should not kill
>processes in presence of swaths of immediately freeable vnodes.

As long as you don't exceed maxvnodes (a value that got larger in
netbsd-10), almost nothing is freed.