K 10 svn:author V 3 snb K 8 svn:date V 27 2009-06-03T09:44:22.636906Z K 7 svn:log V 512 Add vm_lowmem event handler for dirhash. This will cause dirhashes to be deleted when the system is low on memory. This ought to allow an increase to vfs.ufs.dirhash_maxmem on machines that have lots of memory, without degrading performance by having too much memory reserved for dirhash when other things need it. The default value for dirhash_maxmem is being kept at 2MB for now, though. This work was mostly done during the 2008 Google Summer of Code. Approved by: dwmalone (mentor), re MFC after: 3 months END