src/sys_kernel_mm_ksm.c

   1 #include "common.h"
   2
   3 typedef struct ksm_name_value {
   4         char filename[FILENAME_MAX + 1];
   5         unsigned long long value;
   6 } KSM_NAME_VALUE;
   7
   8 #define PAGES_SHARED 0
   9 #define PAGES_SHARING 1
  10 #define PAGES_UNSHARED 2
  11 #define PAGES_VOLATILE 3
  12 #define PAGES_TO_SCAN 4
  13
  14 KSM_NAME_VALUE values[] = {
  15                 [PAGES_SHARED] = { "/sys/kernel/mm/ksm/pages_shared", 0ULL },
  16                 [PAGES_SHARING] = { "/sys/kernel/mm/ksm/pages_sharing", 0ULL },
  17                 [PAGES_UNSHARED] = { "/sys/kernel/mm/ksm/pages_unshared", 0ULL },
  18                 [PAGES_VOLATILE] = { "/sys/kernel/mm/ksm/pages_volatile", 0ULL },
  19                 [PAGES_TO_SCAN] = { "/sys/kernel/mm/ksm/pages_to_scan", 0ULL },
  20 };
  21
  22 int do_sys_kernel_mm_ksm(int update_every, unsigned long long dt) {
  23         static procfile *ff_pages_shared = NULL, *ff_pages_sharing = NULL, *ff_pages_unshared = NULL, *ff_pages_volatile = NULL, *ff_pages_to_scan = NULL;
  24         static long page_size = -1;
  25
  26         if(dt) {};
  27
  28         if(page_size == -1)
  29                 page_size = sysconf(_SC_PAGESIZE);
  30
  31         if(!ff_pages_shared) {
  32                 snprintfz(values[PAGES_SHARED].filename, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/kernel/mm/ksm/pages_shared");
  33                 snprintfz(values[PAGES_SHARED].filename, FILENAME_MAX, "%s", config_get("plugin:proc:/sys/kernel/mm/ksm", "/sys/kernel/mm/ksm/pages_shared", values[PAGES_SHARED].filename));
  34                 ff_pages_shared = procfile_open(values[PAGES_SHARED].filename, " \t:", PROCFILE_FLAG_DEFAULT);
  35         }
  36
  37         if(!ff_pages_sharing) {
  38                 snprintfz(values[PAGES_SHARING].filename, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/kernel/mm/ksm/pages_sharing");
  39                 snprintfz(values[PAGES_SHARING].filename, FILENAME_MAX, "%s", config_get("plugin:proc:/sys/kernel/mm/ksm", "/sys/kernel/mm/ksm/pages_sharing", values[PAGES_SHARING].filename));
  40                 ff_pages_sharing = procfile_open(values[PAGES_SHARING].filename, " \t:", PROCFILE_FLAG_DEFAULT);
  41         }
  42
  43         if(!ff_pages_unshared) {
  44                 snprintfz(values[PAGES_UNSHARED].filename, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/kernel/mm/ksm/pages_unshared");
  45                 snprintfz(values[PAGES_UNSHARED].filename, FILENAME_MAX, "%s", config_get("plugin:proc:/sys/kernel/mm/ksm", "/sys/kernel/mm/ksm/pages_unshared", values[PAGES_UNSHARED].filename));
  46                 ff_pages_unshared = procfile_open(values[PAGES_UNSHARED].filename, " \t:", PROCFILE_FLAG_DEFAULT);
  47         }
  48
  49         if(!ff_pages_volatile) {
  50                 snprintfz(values[PAGES_VOLATILE].filename, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/kernel/mm/ksm/pages_volatile");
  51                 snprintfz(values[PAGES_VOLATILE].filename, FILENAME_MAX, "%s", config_get("plugin:proc:/sys/kernel/mm/ksm", "/sys/kernel/mm/ksm/pages_volatile", values[PAGES_VOLATILE].filename));
  52                 ff_pages_volatile = procfile_open(values[PAGES_VOLATILE].filename, " \t:", PROCFILE_FLAG_DEFAULT);
  53         }
  54
  55         if(!ff_pages_to_scan) {
  56                 snprintfz(values[PAGES_TO_SCAN].filename, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/kernel/mm/ksm/pages_to_scan");
  57                 snprintfz(values[PAGES_TO_SCAN].filename, FILENAME_MAX, "%s", config_get("plugin:proc:/sys/kernel/mm/ksm", "/sys/kernel/mm/ksm/pages_to_scan", values[PAGES_TO_SCAN].filename));
  58                 ff_pages_to_scan = procfile_open(values[PAGES_TO_SCAN].filename, " \t:", PROCFILE_FLAG_DEFAULT);
  59         }
  60
  61         if(!ff_pages_shared || !ff_pages_sharing || !ff_pages_unshared || !ff_pages_volatile || !ff_pages_to_scan) return 1;
  62
  63         unsigned long long pages_shared = 0, pages_sharing = 0, pages_unshared = 0, pages_volatile = 0, pages_to_scan = 0, offered = 0, saved = 0;
  64
  65         ff_pages_shared = procfile_readall(ff_pages_shared);
  66         if(!ff_pages_shared) return 0; // we return 0, so that we will retry to open it next time
  67         pages_shared = strtoull(procfile_lineword(ff_pages_shared, 0, 0), NULL, 10);
  68
  69         ff_pages_sharing = procfile_readall(ff_pages_sharing);
  70         if(!ff_pages_sharing) return 0; // we return 0, so that we will retry to open it next time
  71         pages_sharing = strtoull(procfile_lineword(ff_pages_sharing, 0, 0), NULL, 10);
  72
  73         ff_pages_unshared = procfile_readall(ff_pages_unshared);
  74         if(!ff_pages_unshared) return 0; // we return 0, so that we will retry to open it next time
  75         pages_unshared = strtoull(procfile_lineword(ff_pages_unshared, 0, 0), NULL, 10);
  76
  77         ff_pages_volatile = procfile_readall(ff_pages_volatile);
  78         if(!ff_pages_volatile) return 0; // we return 0, so that we will retry to open it next time
  79         pages_volatile = strtoull(procfile_lineword(ff_pages_volatile, 0, 0), NULL, 10);
  80
  81         ff_pages_to_scan = procfile_readall(ff_pages_to_scan);
  82         if(!ff_pages_to_scan) return 0; // we return 0, so that we will retry to open it next time
  83         pages_to_scan = strtoull(procfile_lineword(ff_pages_to_scan, 0, 0), NULL, 10);
  84
  85         offered = pages_sharing + pages_shared + pages_unshared + pages_volatile;
  86         saved = pages_sharing - pages_shared;
  87
  88         if(!offered || !pages_to_scan) return 0;
  89
  90         RRDSET *st;
  91
  92         // --------------------------------------------------------------------
  93
  94         st = rrdset_find("mem.ksm");
  95         if(!st) {
  96                 st = rrdset_create("mem", "ksm", NULL, "ksm", NULL, "Kernel Same Page Merging", "MB", 5000, update_every, RRDSET_TYPE_AREA);
  97
  98                 rrddim_add(st, "shared", NULL, 1, 1024 * 1024, RRDDIM_ABSOLUTE);
  99                 rrddim_add(st, "unshared", NULL, -1, 1024 * 1024, RRDDIM_ABSOLUTE);
 100                 rrddim_add(st, "sharing", NULL, 1, 1024 * 1024, RRDDIM_ABSOLUTE);
 101                 rrddim_add(st, "volatile", NULL, -1, 1024 * 1024, RRDDIM_ABSOLUTE);
 102                 rrddim_add(st, "to_scan", "to scan", -1, 1024 * 1024, RRDDIM_ABSOLUTE);
 103         }
 104         else rrdset_next(st);
 105
 106         rrddim_set(st, "shared", pages_shared * page_size);
 107         rrddim_set(st, "unshared", pages_unshared * page_size);
 108         rrddim_set(st, "sharing", pages_sharing * page_size);
 109         rrddim_set(st, "volatile", pages_volatile * page_size);
 110         rrddim_set(st, "to_scan", pages_to_scan * page_size);
 111         rrdset_done(st);
 112
 113         st = rrdset_find("mem.ksm_savings");
 114         if(!st) {
 115                 st = rrdset_create("mem", "ksm_savings", NULL, "ksm", NULL, "Kernel Same Page Merging Savings", "MB", 5001, update_every, RRDSET_TYPE_AREA);
 116
 117                 rrddim_add(st, "savings", NULL, -1, 1024 * 1024, RRDDIM_ABSOLUTE);
 118                 rrddim_add(st, "offered", NULL, 1, 1024 * 1024, RRDDIM_ABSOLUTE);
 119         }
 120         else rrdset_next(st);
 121
 122         rrddim_set(st, "savings", saved * page_size);
 123         rrddim_set(st, "offered", offered * page_size);
 124         rrdset_done(st);
 125
 126         st = rrdset_find("mem.ksm_ratios");
 127         if(!st) {
 128                 st = rrdset_create("mem", "ksm_ratios", NULL, "ksm", NULL, "Kernel Same Page Merging Effectiveness", "percentage", 5002, update_every, RRDSET_TYPE_LINE);
 129
 130                 rrddim_add(st, "savings", NULL, 1, 10000, RRDDIM_ABSOLUTE);
 131         }
 132         else rrdset_next(st);
 133
 134         rrddim_set(st, "savings", (saved * 1000000) / offered);
 135         rrdset_done(st);
 136
 137         return 0;
 138 }