xref: /freebsd/sys/sys/vmmeter.h (revision 39beb93c)
1 /*-
2  * Copyright (c) 1982, 1986, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	@(#)vmmeter.h	8.2 (Berkeley) 7/10/94
30  * $FreeBSD$
31  */
32 
33 #ifndef _SYS_VMMETER_H_
34 #define _SYS_VMMETER_H_
35 
36 /*
37  * System wide statistics counters.
38  * Locking:
39  *      a - locked by atomic operations
40  *      c - constant after initialization
41  *      f - locked by vm_page_queue_free_mtx
42  *      p - locked by being in the PCPU and atomicity respect to interrupts
43  *      q - locked by vm_page_queue_mtx
44  */
45 struct vmmeter {
46 	/*
47 	 * General system activity.
48 	 */
49 	u_int v_swtch;		/* (p) context switches */
50 	u_int v_trap;		/* (p) calls to trap */
51 	u_int v_syscall;	/* (p) calls to syscall() */
52 	u_int v_intr;		/* (p) device interrupts */
53 	u_int v_soft;		/* (p) software interrupts */
54 	/*
55 	 * Virtual memory activity.
56 	 */
57 	u_int v_vm_faults;	/* (p) address memory faults */
58 	u_int v_cow_faults;	/* (p) copy-on-writes faults */
59 	u_int v_cow_optim;	/* (p) optimized copy-on-writes faults */
60 	u_int v_zfod;		/* (p) pages zero filled on demand */
61 	u_int v_ozfod;		/* (p) optimized zero fill pages */
62 	u_int v_swapin;		/* (p) swap pager pageins */
63 	u_int v_swapout;	/* (p) swap pager pageouts */
64 	u_int v_swappgsin;	/* (p) swap pager pages paged in */
65 	u_int v_swappgsout;	/* (p) swap pager pages paged out */
66 	u_int v_vnodein;	/* (p) vnode pager pageins */
67 	u_int v_vnodeout;	/* (p) vnode pager pageouts */
68 	u_int v_vnodepgsin;	/* (p) vnode_pager pages paged in */
69 	u_int v_vnodepgsout;	/* (p) vnode pager pages paged out */
70 	u_int v_intrans;	/* (p) intransit blocking page faults */
71 	u_int v_reactivated;	/* (f) pages reactivated from free list */
72 	u_int v_pdwakeups;	/* (f) times daemon has awaken from sleep */
73 	u_int v_pdpages;	/* (q) pages analyzed by daemon */
74 
75 	u_int v_tcached;	/* (q) total pages cached */
76 	u_int v_dfree;		/* (q) pages freed by daemon */
77 	u_int v_pfree;		/* (q) pages freed by exiting processes */
78 	u_int v_tfree;		/* (p) total pages freed */
79 	/*
80 	 * Distribution of page usages.
81 	 */
82 	u_int v_page_size;	/* (c) page size in bytes */
83 	u_int v_page_count;	/* (c) total number of pages in system */
84 	u_int v_free_reserved;	/* (c) pages reserved for deadlock */
85 	u_int v_free_target;	/* (c) pages desired free */
86 	u_int v_free_min;	/* (c) pages desired free */
87 	u_int v_free_count;	/* (f) pages free */
88 	u_int v_wire_count;	/* (a) pages wired down */
89 	u_int v_active_count;	/* (q) pages active */
90 	u_int v_inactive_target; /* (c) pages desired inactive */
91 	u_int v_inactive_count;	/* (q) pages inactive */
92 	u_int v_cache_count;	/* (f) pages on cache queue */
93 	u_int v_cache_min;	/* (c) min pages desired on cache queue */
94 	u_int v_cache_max;	/* (c) max pages in cached obj */
95 	u_int v_pageout_free_min;   /* (c) min pages reserved for kernel */
96 	u_int v_interrupt_free_min; /* (c) reserved pages for int code */
97 	u_int v_free_severe;	/* (c) severe page depletion point */
98 	/*
99 	 * Fork/vfork/rfork activity.
100 	 */
101 	u_int v_forks;		/* (p) fork() calls */
102 	u_int v_vforks;		/* (p) vfork() calls */
103 	u_int v_rforks;		/* (p) rfork() calls */
104 	u_int v_kthreads;	/* (p) fork() calls by kernel */
105 	u_int v_forkpages;	/* (p) VM pages affected by fork() */
106 	u_int v_vforkpages;	/* (p) VM pages affected by vfork() */
107 	u_int v_rforkpages;	/* (p) VM pages affected by rfork() */
108 	u_int v_kthreadpages;	/* (p) VM pages affected by fork() by kernel */
109 };
110 #ifdef _KERNEL
111 
112 extern struct vmmeter cnt;
113 
114 /*
115  * Return TRUE if we are under our severe low-free-pages threshold
116  *
117  * This routine is typically used at the user<->system interface to determine
118  * whether we need to block in order to avoid a low memory deadlock.
119  */
120 
121 static __inline
122 int
123 vm_page_count_severe(void)
124 {
125     return (cnt.v_free_severe > (cnt.v_free_count + cnt.v_cache_count));
126 }
127 
128 /*
129  * Return TRUE if we are under our minimum low-free-pages threshold.
130  *
131  * This routine is typically used within the system to determine whether
132  * we can execute potentially very expensive code in terms of memory.  It
133  * is also used by the pageout daemon to calculate when to sleep, when
134  * to wake waiters up, and when (after making a pass) to become more
135  * desparate.
136  */
137 
138 static __inline
139 int
140 vm_page_count_min(void)
141 {
142     return (cnt.v_free_min > (cnt.v_free_count + cnt.v_cache_count));
143 }
144 
145 /*
146  * Return TRUE if we have not reached our free page target during
147  * free page recovery operations.
148  */
149 
150 static __inline
151 int
152 vm_page_count_target(void)
153 {
154     return (cnt.v_free_target > (cnt.v_free_count + cnt.v_cache_count));
155 }
156 
157 /*
158  * Return the number of pages we need to free-up or cache
159  * A positive number indicates that we do not have enough free pages.
160  */
161 
162 static __inline
163 int
164 vm_paging_target(void)
165 {
166     return (
167 	(cnt.v_free_target + cnt.v_cache_min) -
168 	(cnt.v_free_count + cnt.v_cache_count)
169     );
170 }
171 
172 /*
173  * Returns TRUE if the pagedaemon needs to be woken up.
174  */
175 
176 static __inline
177 int
178 vm_paging_needed(void)
179 {
180     return (
181 	(cnt.v_free_reserved + cnt.v_cache_min) >
182 	(cnt.v_free_count + cnt.v_cache_count)
183     );
184 }
185 
186 #endif
187 
188 /* systemwide totals computed every five seconds */
189 struct vmtotal {
190 	int16_t	t_rq;		/* length of the run queue */
191 	int16_t	t_dw;		/* jobs in ``disk wait'' (neg priority) */
192 	int16_t	t_pw;		/* jobs in page wait */
193 	int16_t	t_sl;		/* jobs sleeping in core */
194 	int16_t	t_sw;		/* swapped out runnable/short block jobs */
195 	int32_t	t_vm;		/* total virtual memory */
196 	int32_t	t_avm;		/* active virtual memory */
197 	int32_t	t_rm;		/* total real memory in use */
198 	int32_t	t_arm;		/* active real memory */
199 	int32_t	t_vmshr;	/* shared virtual memory */
200 	int32_t	t_avmshr;	/* active shared virtual memory */
201 	int32_t	t_rmshr;	/* shared real memory */
202 	int32_t	t_armshr;	/* active shared real memory */
203 	int32_t	t_free;		/* free memory pages */
204 };
205 
206 #endif
207