management for VM objects

Vagner vagner at
Tue Oct 30 21:03:56 UTC 2012

This questions about Inactive queue and Swap layer in VM management
system at FreeBSD. For test, i running dd (for put ufs cache to Inactive), and i get this:

1132580 wire
896796 act
5583964 inact
281852 cache
112252 free
836960 buf

in swap: 20M

It is good. Lets start run programm like:

typedef char * pchar;
pchar a[1024*1024*4];
for(size_t i = 0; i < 1024*1024*2; i++)
	a[i] = (pchar)malloc(1024);
	if(a[i]) *(a[i]) = 'F';

Get this:

1156420 wire
3070196 act
3465316 inact
206352 cache
109160 free
836960 buf

in swap: 20M

After i call free() pages put to free.

But, why condition is not satisfied from this page:
My durty pages don't written to their backing store before being
reusable. I don't understeand this:(

Stanislav Putrya
System administrator
FotoStrana.Ru Ltd.
ICQ IM: 328585847
Jabber-GoogleTalk: root.vagner SPB: +79215788755 RND: +79525600664
email: vagner at
email: putrya at
email: root.vagner at

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