src/collectors/proc.plugin/proc_pressure.c
// SPDX-License-Identifier: GPL-3.0-or-later
#include "plugin_proc.h"
#define PLUGIN_PROC_MODULE_PRESSURE_NAME "/proc/pressure"
#define CONFIG_SECTION_PLUGIN_PROC_PRESSURE "plugin:" PLUGIN_PROC_CONFIG_NAME ":" PLUGIN_PROC_MODULE_PRESSURE_NAME
// linux calculates this every 2 seconds, see kernel/sched/psi.c PSI_FREQ
#define MIN_PRESSURE_UPDATE_EVERY 2
static int pressure_update_every = 0;
static struct pressure resources[PRESSURE_NUM_RESOURCES] = {
{
.some = {
.available = true,
.share_time = {.id = "cpu_some_pressure", .title = "CPU some pressure"},
.total_time = {.id = "cpu_some_pressure_stall_time", .title = "CPU some pressure stall time"}
},
.full = {
// Disable CPU full pressure.
// See https://github.com/torvalds/linux/commit/890d550d7dbac7a31ecaa78732aa22be282bb6b8
.available = false,
.share_time = {.id = "cpu_full_pressure", .title = "CPU full pressure"},
.total_time = {.id = "cpu_full_pressure_stall_time", .title = "CPU full pressure stall time"}
},
},
{
.some = {
.available = true,
.share_time = {.id = "memory_some_pressure", .title = "Memory some pressure"},
.total_time = {.id = "memory_some_pressure_stall_time", .title = "Memory some pressure stall time"}
},
.full = {
.available = true,
.share_time = {.id = "memory_full_pressure", .title = "Memory full pressure"},
.total_time = {.id = "memory_full_pressure_stall_time", .title = "Memory full pressure stall time"}
},
},
{
.some = {
.available = true,
.share_time = {.id = "io_some_pressure", .title = "I/O some pressure"},
.total_time = {.id = "io_some_pressure_stall_time", .title = "I/O some pressure stall time"}
},
.full = {
.available = true,
.share_time = {.id = "io_full_pressure", .title = "I/O full pressure"},
.total_time = {.id = "io_full_pressure_stall_time", .title = "I/O full pressure stall time"}
},
},
{
.some = {
// this is not available
.available = false,
.share_time = {.id = "irq_some_pressure", .title = "IRQ some pressure"},
.total_time = {.id = "irq_some_pressure_stall_time", .title = "IRQ some pressure stall time"}
},
.full = {
.available = true,
.share_time = {.id = "irq_full_pressure", .title = "IRQ full pressure"},
.total_time = {.id = "irq_full_pressure_stall_time", .title = "IRQ full pressure stall time"}
},
},
};
static struct resource_info {
procfile *pf;
const char *name; // metric file name
const char *family; // webui section name
int section_priority;
} resource_info[PRESSURE_NUM_RESOURCES] = {
{ .name = "cpu", .family = "cpu", .section_priority = NETDATA_CHART_PRIO_SYSTEM_CPU },
{ .name = "memory", .family = "ram", .section_priority = NETDATA_CHART_PRIO_SYSTEM_RAM },
{ .name = "io", .family = "disk", .section_priority = NETDATA_CHART_PRIO_SYSTEM_IO },
{ .name = "irq", .family = "interrupts", .section_priority = NETDATA_CHART_PRIO_SYSTEM_INTERRUPTS },
};
void update_pressure_charts(struct pressure_charts *pcs) {
if (pcs->share_time.st) {
rrddim_set_by_pointer(
pcs->share_time.st, pcs->share_time.rd10, (collected_number)(pcs->share_time.value10 * 100));
rrddim_set_by_pointer(
pcs->share_time.st, pcs->share_time.rd60, (collected_number)(pcs->share_time.value60 * 100));
rrddim_set_by_pointer(
pcs->share_time.st, pcs->share_time.rd300, (collected_number)(pcs->share_time.value300 * 100));
rrdset_done(pcs->share_time.st);
}
if (pcs->total_time.st) {
rrddim_set_by_pointer(
pcs->total_time.st, pcs->total_time.rdtotal, (collected_number)(pcs->total_time.value_total));
rrdset_done(pcs->total_time.st);
}
}
static void proc_pressure_do_resource(procfile *ff, int res_idx, size_t line, bool some) {
struct pressure_charts *pcs;
struct resource_info ri;
pcs = some ? &resources[res_idx].some : &resources[res_idx].full;
ri = resource_info[res_idx];
if (unlikely(!pcs->share_time.st)) {
pcs->share_time.st = rrdset_create_localhost(
"system",
pcs->share_time.id,
NULL,
ri.family,
NULL,
pcs->share_time.title,
"percentage",
PLUGIN_PROC_NAME,
PLUGIN_PROC_MODULE_PRESSURE_NAME,
ri.section_priority + (some ? 40 : 50),
pressure_update_every,
RRDSET_TYPE_LINE);
pcs->share_time.rd10 =
rrddim_add(pcs->share_time.st, some ? "some 10" : "full 10", NULL, 1, 100, RRD_ALGORITHM_ABSOLUTE);
pcs->share_time.rd60 =
rrddim_add(pcs->share_time.st, some ? "some 60" : "full 60", NULL, 1, 100, RRD_ALGORITHM_ABSOLUTE);
pcs->share_time.rd300 =
rrddim_add(pcs->share_time.st, some ? "some 300" : "full 300", NULL, 1, 100, RRD_ALGORITHM_ABSOLUTE);
}
pcs->share_time.value10 = strtod(procfile_lineword(ff, line, 2), NULL);
pcs->share_time.value60 = strtod(procfile_lineword(ff, line, 4), NULL);
pcs->share_time.value300 = strtod(procfile_lineword(ff, line, 6), NULL);
if (unlikely(!pcs->total_time.st)) {
pcs->total_time.st = rrdset_create_localhost(
"system",
pcs->total_time.id,
NULL,
ri.family,
NULL,
pcs->total_time.title,
"ms",
PLUGIN_PROC_NAME,
PLUGIN_PROC_MODULE_PRESSURE_NAME,
ri.section_priority + (some ? 45 : 55),
pressure_update_every,
RRDSET_TYPE_LINE);
pcs->total_time.rdtotal = rrddim_add(pcs->total_time.st, "time", NULL, 1, 1, RRD_ALGORITHM_INCREMENTAL);
}
pcs->total_time.value_total = str2ull(procfile_lineword(ff, line, 8), NULL) / 1000;
}
static void proc_pressure_do_resource_some(procfile *ff, int res_idx, size_t line) {
proc_pressure_do_resource(ff, res_idx, line, true);
}
static void proc_pressure_do_resource_full(procfile *ff, int res_idx, size_t line) {
proc_pressure_do_resource(ff, res_idx, line, false);
}
int do_proc_pressure(int update_every, usec_t dt) {
int ok_count = 0;
int i;
static usec_t next_pressure_dt = 0;
static char *base_path = NULL;
update_every = (update_every < MIN_PRESSURE_UPDATE_EVERY) ? MIN_PRESSURE_UPDATE_EVERY : update_every;
pressure_update_every = update_every;
if (next_pressure_dt <= dt) {
next_pressure_dt = update_every * USEC_PER_SEC;
} else {
next_pressure_dt -= dt;
return 0;
}
if (unlikely(!base_path)) {
base_path = config_get(CONFIG_SECTION_PLUGIN_PROC_PRESSURE, "base path of pressure metrics", "/proc/pressure");
}
for (i = 0; i < PRESSURE_NUM_RESOURCES; i++) {
procfile *ff = resource_info[i].pf;
int do_some = resources[i].some.enabled, do_full = resources[i].full.enabled;
if (!resources[i].some.available && !resources[i].full.available)
continue;
if (unlikely(!ff)) {
char filename[FILENAME_MAX + 1];
char config_key[CONFIG_MAX_NAME + 1];
snprintfz(filename
, FILENAME_MAX
, "%s%s/%s"
, netdata_configured_host_prefix
, base_path
, resource_info[i].name);
do_some = resources[i].some.available ? CONFIG_BOOLEAN_YES : CONFIG_BOOLEAN_NO;
do_full = resources[i].full.available ? CONFIG_BOOLEAN_YES : CONFIG_BOOLEAN_NO;
snprintfz(config_key, CONFIG_MAX_NAME, "enable %s some pressure", resource_info[i].name);
do_some = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_PRESSURE, config_key, do_some);
resources[i].some.enabled = do_some;
snprintfz(config_key, CONFIG_MAX_NAME, "enable %s full pressure", resource_info[i].name);
do_full = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_PRESSURE, config_key, do_full);
resources[i].full.enabled = do_full;
if (!do_full && !do_some) {
resources[i].some.available = false;
resources[i].full.available = false;
continue;
}
ff = procfile_open(filename, " =", PROCFILE_FLAG_NO_ERROR_ON_FILE_IO);
if (unlikely(!ff)) {
// PSI IRQ was added recently (https://github.com/torvalds/linux/commit/52b1364ba0b105122d6de0e719b36db705011ac1)
if (strcmp(resource_info[i].name, "irq") != 0)
collector_error("Cannot read pressure information from %s.", filename);
resources[i].some.available = false;
resources[i].full.available = false;
continue;
}
}
ff = procfile_readall(ff);
resource_info[i].pf = ff;
if (unlikely(!ff))
continue;
size_t lines = procfile_lines(ff);
if (unlikely(lines < 1)) {
collector_error("%s has no lines.", procfile_filename(ff));
continue;
}
for(size_t l = 0; l < lines ;l++) {
const char *key = procfile_lineword(ff, l, 0);
if(strcmp(key, "some") == 0) {
if(do_some) {
proc_pressure_do_resource_some(ff, i, l);
update_pressure_charts(&resources[i].some);
ok_count++;
}
}
else if(strcmp(key, "full") == 0) {
if(do_full) {
proc_pressure_do_resource_full(ff, i, l);
update_pressure_charts(&resources[i].full);
ok_count++;
}
}
}
}
if(!ok_count)
return 1;
return 0;
}