procps/library/include/slabinfo.h
Zhao Mengmeng 25cd1bee0c slabinfo: add comment for cache_size calculation
One of our physical machine shows that the "CACHE SIZE" column
of slabtop output is extremely high, three times of the products
of objs nums and objs size. After some analysis, we found that
the order of slab, which decides "pages per slab", will shrink
when memory pressure is high and normal order allocation failed.
So we think it might help to add these comments to the man help.

Minor fix: add the "memory." back, which is lost after
"aa461df0: docs: Minor manpage fixes"

Signed-off-by: Zhao Mengmeng <zhaomengmeng@kylinos.cn>
2023-04-25 07:19:22 +00:00

141 lines
4.8 KiB
C

/*
* slabinfo.h - slab pools related declarations for libproc2
*
* Copyright © 2015-2023 Jim Warner <james.warner@comcast.net>
* Copyright © 2015-2023 Craig Small <csmall@dropbear.xyz>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef PROCPS_SLABINFO_H
#define PROCPS_SLABINFO_H
#ifdef __cplusplus
extern "C "{
#endif
enum slabinfo_item {
SLABINFO_noop, // ( never altered )
SLABINFO_extra, // ( reset to zero )
// returns origin, see proc(5)
// ------- -------------------
SLAB_NAME, // str /proc/slabinfo
SLAB_NUM_OBJS, // u_int "
SLAB_ACTIVE_OBJS, // u_int "
SLAB_OBJ_SIZE, // u_int "
SLAB_OBJ_PER_SLAB, // u_int "
SLAB_NUMS_SLABS, // u_int "
SLAB_ACTIVE_SLABS, // u_int "
SLAB_PAGES_PER_SLAB, // u_int "
SLAB_PERCENT_USED, // u_int derived from ACTIVE_OBJS / NUM_OBJS
SLAB_SIZE_TOTAL, // ul_int derived from page size * NUMS_SLABS * PAGES_PER_SLAB
SLABS_CACHES_TOTAL, // u_int derived from all caches
SLABS_CACHES_ACTIVE, // u_int "
SLABS_NUM_OBJS, // u_int "
SLABS_ACTIVE_OBJS, // u_int "
SLABS_OBJ_SIZE_AVG, // u_int "
SLABS_OBJ_SIZE_MIN, // u_int "
SLABS_OBJ_SIZE_MAX, // u_int "
SLABS_NUMS_SLABS, // u_int "
SLABS_ACTIVE_SLABS, // u_int "
SLABS_PAGES_TOTAL, // u_int "
SLABS_SIZE_ACTIVE, // ul_int "
SLABS_SIZE_TOTAL, // ul_int "
SLABS_DELTA_CACHES_TOTAL, // s_int derived from above
SLABS_DELTA_CACHES_ACTIVE, // s_int "
SLABS_DELTA_NUM_OBJS, // s_int "
SLABS_DELTA_ACTIVE_OBJS, // s_int "
SLABS_DELTA_OBJ_SIZE_AVG, // s_int "
SLABS_DELTA_OBJ_SIZE_MIN, // s_int "
SLABS_DELTA_OBJ_SIZE_MAX, // s_int "
SLABS_DELTA_NUMS_SLABS, // s_int "
SLABS_DELTA_ACTIVE_SLABS, // s_int "
SLABS_DELTA_PAGES_TOTAL, // s_int "
SLABS_DELTA_SIZE_ACTIVE, // s_int "
SLABS_DELTA_SIZE_TOTAL // s_int "
};
enum slabinfo_sort_order {
SLABINFO_SORT_ASCEND = +1,
SLABINFO_SORT_DESCEND = -1
};
struct slabinfo_result {
enum slabinfo_item item;
union {
signed int s_int;
unsigned int u_int;
unsigned long ul_int;
char *str;
} result;
};
struct slabinfo_stack {
struct slabinfo_result *head;
};
struct slabinfo_reaped {
int total;
struct slabinfo_stack **stacks;
};
struct slabinfo_info;
#define SLABINFO_GET( info, actual_enum, type ) ( { \
struct slabinfo_result *r = procps_slabinfo_get( info, actual_enum ); \
r ? r->result . type : 0; } )
#define SLABINFO_VAL( relative_enum, type, stack, info ) \
stack -> head [ relative_enum ] . result . type
int procps_slabinfo_new (struct slabinfo_info **info);
int procps_slabinfo_ref (struct slabinfo_info *info);
int procps_slabinfo_unref (struct slabinfo_info **info);
struct slabinfo_result *procps_slabinfo_get (
struct slabinfo_info *info,
enum slabinfo_item item);
struct slabinfo_reaped *procps_slabinfo_reap (
struct slabinfo_info *info,
enum slabinfo_item *items,
int numitems);
struct slabinfo_stack *procps_slabinfo_select (
struct slabinfo_info *info,
enum slabinfo_item *items,
int numitems);
struct slabinfo_stack **procps_slabinfo_sort (
struct slabinfo_info *info,
struct slabinfo_stack *stacks[],
int numstacked,
enum slabinfo_item sortitem,
enum slabinfo_sort_order order);
#ifdef XTRA_PROCPS_DEBUG
# include "xtra-procps-debug.h"
#endif
#ifdef __cplusplus
}
#endif
#endif