Adding upstream version 1.44.3.upstream/1.44.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 520 insertions, 0 deletions

diff --git a/collectors/cgroups.plugin/cgroup-top.c b/collectors/cgroups.plugin/cgroup-top.c
new file mode 100644
index 00000000..8d44d3b5
--- /dev/null
+++ b/collectors/cgroups.plugin/cgroup-top.c
@@ -0,0 +1,520 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "cgroup-internals.h"
+
+struct cgroup_netdev_link {
+    size_t read_slot;
+    NETDATA_DOUBLE received[2];
+    NETDATA_DOUBLE sent[2];
+};
+
+static DICTIONARY *cgroup_netdev_link_dict = NULL;
+
+void cgroup_netdev_link_init(void) {
+    cgroup_netdev_link_dict = dictionary_create_advanced(DICT_OPTION_FIXED_SIZE|DICT_OPTION_DONT_OVERWRITE_VALUE, NULL, sizeof(struct cgroup_netdev_link));
+}
+
+const DICTIONARY_ITEM *cgroup_netdev_get(struct cgroup *cg) {
+    if(!cg->cgroup_netdev_link) {
+        struct cgroup_netdev_link t = {
+            .read_slot = 0,
+            .received = {NAN, NAN},
+            .sent = {NAN, NAN},
+        };
+
+        cg->cgroup_netdev_link =
+            dictionary_set_and_acquire_item(cgroup_netdev_link_dict, cg->id, &t, sizeof(struct cgroup_netdev_link));
+    }
+
+    return dictionary_acquired_item_dup(cgroup_netdev_link_dict, cg->cgroup_netdev_link);
+}
+
+void cgroup_netdev_delete(struct cgroup *cg) {
+    if(cg->cgroup_netdev_link) {
+        dictionary_acquired_item_release(cgroup_netdev_link_dict, cg->cgroup_netdev_link);
+        dictionary_del(cgroup_netdev_link_dict, cg->id);
+        dictionary_garbage_collect(cgroup_netdev_link_dict);
+        cg->cgroup_netdev_link = NULL;
+    }
+}
+
+void cgroup_netdev_release(const DICTIONARY_ITEM *link) {
+    if(link)
+        dictionary_acquired_item_release(cgroup_netdev_link_dict, link);
+}
+
+const void *cgroup_netdev_dup(const DICTIONARY_ITEM *link) {
+    return dictionary_acquired_item_dup(cgroup_netdev_link_dict, link);
+}
+
+void cgroup_netdev_reset_all(void) {
+    struct cgroup_netdev_link *t;
+    dfe_start_read(cgroup_netdev_link_dict, t) {
+        if(t->read_slot >= 1) {
+            t->read_slot = 0;
+            t->received[1] = NAN;
+            t->sent[1] = NAN;
+        }
+        else {
+            t->read_slot = 1;
+            t->received[0] = NAN;
+            t->sent[0] = NAN;
+        }
+    }
+    dfe_done(t);
+}
+
+void cgroup_netdev_add_bandwidth(const DICTIONARY_ITEM *link, NETDATA_DOUBLE received, NETDATA_DOUBLE sent) {
+    if(!link)
+        return;
+
+    struct cgroup_netdev_link *t = dictionary_acquired_item_value(link);
+
+    size_t slot = (t->read_slot) ? 0 : 1;
+
+    if(isnan(t->received[slot]))
+        t->received[slot] = received;
+    else
+        t->received[slot] += received;
+
+    if(isnan(t->sent[slot]))
+        t->sent[slot] = sent;
+    else
+        t->sent[slot] += sent;
+}
+
+void cgroup_netdev_get_bandwidth(struct cgroup *cg, NETDATA_DOUBLE *received, NETDATA_DOUBLE *sent) {
+    if(!cg->cgroup_netdev_link) {
+        *received = NAN;
+        *sent = NAN;
+        return;
+    }
+
+    struct cgroup_netdev_link *t = dictionary_acquired_item_value(cg->cgroup_netdev_link);
+
+    size_t slot = (t->read_slot) ? 1 : 0;
+
+    *received = t->received[slot];
+    *sent = t->sent[slot];
+}
+
+int cgroup_function_cgroup_top(BUFFER *wb, int timeout __maybe_unused, const char *function __maybe_unused,
+        void *collector_data __maybe_unused,
+        rrd_function_result_callback_t result_cb, void *result_cb_data,
+        rrd_function_is_cancelled_cb_t is_cancelled_cb, void *is_cancelled_cb_data,
+        rrd_function_register_canceller_cb_t register_canceller_cb __maybe_unused,
+        void *register_canceller_cb_data __maybe_unused) {
+
+    buffer_flush(wb);
+    wb->content_type = CT_APPLICATION_JSON;
+    buffer_json_initialize(wb, "\"", "\"", 0, true, BUFFER_JSON_OPTIONS_DEFAULT);
+
+    buffer_json_member_add_string(wb, "hostname", rrdhost_hostname(localhost));
+    buffer_json_member_add_uint64(wb, "status", HTTP_RESP_OK);
+    buffer_json_member_add_string(wb, "type", "table");
+    buffer_json_member_add_time_t(wb, "update_every", 1);
+    buffer_json_member_add_string(wb, "help", RRDFUNCTIONS_CGTOP_HELP);
+    buffer_json_member_add_array(wb, "data");
+
+    double max_pids = 0.0;
+    double max_cpu = 0.0;
+    double max_ram = 0.0;
+    double max_disk_io_read = 0.0;
+    double max_disk_io_written = 0.0;
+    double max_net_received = 0.0;
+    double max_net_sent = 0.0;
+
+    RRDDIM *rd = NULL;
+
+    uv_mutex_lock(&cgroup_root_mutex);
+
+    for(struct cgroup *cg = cgroup_root; cg ; cg = cg->next) {
+        if(unlikely(!cg->enabled || cg->pending_renames || !cg->function_ready || is_cgroup_systemd_service(cg)))
+            continue;
+
+        buffer_json_add_array_item_array(wb);
+
+        buffer_json_add_array_item_string(wb, cg->name); // Name
+
+        if(k8s_is_kubepod(cg))
+            buffer_json_add_array_item_string(wb, "k8s"); // Kind
+        else
+            buffer_json_add_array_item_string(wb, "cgroup"); // Kind
+
+        double pids_current = rrddim_get_last_stored_value(cg->st_pids_rd_pids_current, &max_pids, 1.0);
+
+        double cpu = NAN;
+        if (cg->st_cpu_rd_user && cg->st_cpu_rd_system) {
+            cpu = cg->st_cpu_rd_user->collector.last_stored_value + cg->st_cpu_rd_system->collector.last_stored_value;
+            max_cpu = MAX(max_cpu, cpu);
+        }
+
+        double ram = rrddim_get_last_stored_value(cg->st_mem_rd_ram, &max_ram, 1.0);
+
+        rd = cg->st_throttle_io_rd_read ? cg->st_throttle_io_rd_read : cg->st_io_rd_read;
+        double disk_io_read = rrddim_get_last_stored_value(rd, &max_disk_io_read, 1024.0);
+        rd = cg->st_throttle_io_rd_written ? cg->st_throttle_io_rd_written : cg->st_io_rd_written;
+        double disk_io_written = rrddim_get_last_stored_value(rd, &max_disk_io_written, 1024.0);
+
+        NETDATA_DOUBLE received, sent;
+        cgroup_netdev_get_bandwidth(cg, &received, &sent);
+        if (!isnan(received) && !isnan(sent)) {
+            received /= 1000.0;
+            sent /= 1000.0;
+            max_net_received = MAX(max_net_received, received);
+            max_net_sent = MAX(max_net_sent, sent);
+        }
+
+        buffer_json_add_array_item_double(wb, pids_current);
+        buffer_json_add_array_item_double(wb, cpu);
+        buffer_json_add_array_item_double(wb, ram);
+        buffer_json_add_array_item_double(wb, disk_io_read);
+        buffer_json_add_array_item_double(wb, disk_io_written);
+        buffer_json_add_array_item_double(wb, received);
+        buffer_json_add_array_item_double(wb, sent);
+
+        buffer_json_array_close(wb);
+    }
+
+    uv_mutex_unlock(&cgroup_root_mutex);
+
+    buffer_json_array_close(wb); // data
+    buffer_json_member_add_object(wb, "columns");
+    {
+        size_t field_id = 0;
+
+        // Node
+        buffer_rrdf_table_add_field(wb, field_id++, "Name", "CGROUP Name",
+                RRDF_FIELD_TYPE_STRING, RRDF_FIELD_VISUAL_VALUE, RRDF_FIELD_TRANSFORM_NONE,
+                0, NULL, NAN, RRDF_FIELD_SORT_ASCENDING, NULL,
+                RRDF_FIELD_SUMMARY_COUNT, RRDF_FIELD_FILTER_MULTISELECT,
+                RRDF_FIELD_OPTS_VISIBLE | RRDF_FIELD_OPTS_UNIQUE_KEY | RRDF_FIELD_OPTS_STICKY | RRDF_FIELD_OPTS_FULL_WIDTH,
+                NULL);
+
+        // Kind
+        buffer_rrdf_table_add_field(wb, field_id++, "Kind", "CGROUP Kind",
+                RRDF_FIELD_TYPE_STRING, RRDF_FIELD_VISUAL_VALUE, RRDF_FIELD_TRANSFORM_NONE,
+                0, NULL, NAN, RRDF_FIELD_SORT_ASCENDING, NULL,
+                RRDF_FIELD_SUMMARY_COUNT, RRDF_FIELD_FILTER_MULTISELECT,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // PIDs
+        buffer_rrdf_table_add_field(wb, field_id++, "PIDs", "Number of Processes Currently in the CGROUP",
+                RRDF_FIELD_TYPE_INTEGER, RRDF_FIELD_VISUAL_VALUE, RRDF_FIELD_TRANSFORM_NUMBER,
+                0, "pids", max_pids, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // CPU
+        buffer_rrdf_table_add_field(wb, field_id++, "CPU", "CPU Usage",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "%", max_cpu, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // RAM
+        buffer_rrdf_table_add_field(wb, field_id++, "RAM", "RAM Usage",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "MiB", max_ram, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+        
+        // Disk IO Reads
+        buffer_rrdf_table_add_field(wb, field_id++, "Reads", "Disk Read Data",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "MiB", max_disk_io_read, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // Disk IO Writes
+        buffer_rrdf_table_add_field(wb, field_id++, "Writes", "Disk Written Data",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "MiB", max_disk_io_written, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // Network Received
+        buffer_rrdf_table_add_field(wb, field_id++, "Received", "Network Traffic Received",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "Mbps", max_net_received, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // Network Sent
+        buffer_rrdf_table_add_field(wb, field_id++, "Sent", "Network Traffic Sent ",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "Mbps", max_net_sent, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+    }
+    buffer_json_object_close(wb); // columns
+    buffer_json_member_add_string(wb, "default_sort_column", "CPU");
+
+    buffer_json_member_add_object(wb, "charts");
+    {
+        buffer_json_member_add_object(wb, "CPU");
+        {
+            buffer_json_member_add_string(wb, "name", "CPU");
+            buffer_json_member_add_string(wb, "type", "stacked-bar");
+            buffer_json_member_add_array(wb, "columns");
+            {
+                buffer_json_add_array_item_string(wb, "CPU");
+            }
+            buffer_json_array_close(wb);
+        }
+        buffer_json_object_close(wb);
+
+        buffer_json_member_add_object(wb, "Memory");
+        {
+            buffer_json_member_add_string(wb, "name", "Memory");
+            buffer_json_member_add_string(wb, "type", "stacked-bar");
+            buffer_json_member_add_array(wb, "columns");
+            {
+                buffer_json_add_array_item_string(wb, "RAM");
+            }
+            buffer_json_array_close(wb);
+        }
+        buffer_json_object_close(wb);
+
+        buffer_json_member_add_object(wb, "Traffic");
+        {
+            buffer_json_member_add_string(wb, "name", "Traffic");
+            buffer_json_member_add_string(wb, "type", "stacked-bar");
+            buffer_json_member_add_array(wb, "columns");
+            {
+                buffer_json_add_array_item_string(wb, "Received");
+                buffer_json_add_array_item_string(wb, "Sent");
+            }
+            buffer_json_array_close(wb);
+        }
+        buffer_json_object_close(wb);
+    }
+    buffer_json_object_close(wb); // charts
+
+    buffer_json_member_add_array(wb, "default_charts");
+    {
+        buffer_json_add_array_item_array(wb);
+        buffer_json_add_array_item_string(wb, "CPU");
+        buffer_json_add_array_item_string(wb, "Name");
+        buffer_json_array_close(wb);
+
+        buffer_json_add_array_item_array(wb);
+        buffer_json_add_array_item_string(wb, "Memory");
+        buffer_json_add_array_item_string(wb, "Name");
+        buffer_json_array_close(wb);
+    }
+    buffer_json_array_close(wb);
+
+    buffer_json_member_add_object(wb, "group_by");
+    {
+        buffer_json_member_add_object(wb, "Kind");
+        {
+            buffer_json_member_add_string(wb, "name", "Kind");
+            buffer_json_member_add_array(wb, "columns");
+            {
+                buffer_json_add_array_item_string(wb, "Kind");
+            }
+            buffer_json_array_close(wb);
+        }
+        buffer_json_object_close(wb);
+    }
+    buffer_json_object_close(wb); // group_by
+
+    buffer_json_member_add_time_t(wb, "expires", now_realtime_sec() + 1);
+    buffer_json_finalize(wb);
+
+    int response = HTTP_RESP_OK;
+    if(is_cancelled_cb && is_cancelled_cb(is_cancelled_cb_data)) {
+        buffer_flush(wb);
+        response = HTTP_RESP_CLIENT_CLOSED_REQUEST;
+    }
+
+    if(result_cb)
+        result_cb(wb, response, result_cb_data);
+
+    return response;
+}
+
+int cgroup_function_systemd_top(BUFFER *wb, int timeout __maybe_unused, const char *function __maybe_unused,
+        void *collector_data __maybe_unused,
+        rrd_function_result_callback_t result_cb, void *result_cb_data,
+        rrd_function_is_cancelled_cb_t is_cancelled_cb, void *is_cancelled_cb_data,
+        rrd_function_register_canceller_cb_t register_canceller_cb __maybe_unused,
+        void *register_canceller_cb_data __maybe_unused) {
+
+    buffer_flush(wb);
+    wb->content_type = CT_APPLICATION_JSON;
+    buffer_json_initialize(wb, "\"", "\"", 0, true, BUFFER_JSON_OPTIONS_DEFAULT);
+
+    buffer_json_member_add_string(wb, "hostname", rrdhost_hostname(localhost));
+    buffer_json_member_add_uint64(wb, "status", HTTP_RESP_OK);
+    buffer_json_member_add_string(wb, "type", "table");
+    buffer_json_member_add_time_t(wb, "update_every", 1);
+    buffer_json_member_add_string(wb, "help", RRDFUNCTIONS_CGTOP_HELP);
+    buffer_json_member_add_array(wb, "data");
+
+    double max_pids = 0.0;
+    double max_cpu = 0.0;
+    double max_ram = 0.0;
+    double max_disk_io_read = 0.0;
+    double max_disk_io_written = 0.0;
+
+    RRDDIM *rd = NULL;
+
+    uv_mutex_lock(&cgroup_root_mutex);
+
+    for(struct cgroup *cg = cgroup_root; cg ; cg = cg->next) {
+        if(unlikely(!cg->enabled || cg->pending_renames || !cg->function_ready || !is_cgroup_systemd_service(cg)))
+            continue;
+
+        buffer_json_add_array_item_array(wb);
+
+        buffer_json_add_array_item_string(wb, cg->name);
+
+        double pids_current = rrddim_get_last_stored_value(cg->st_pids_rd_pids_current, &max_pids, 1.0);
+
+        double cpu = NAN;
+        if (cg->st_cpu_rd_user && cg->st_cpu_rd_system) {
+            cpu = cg->st_cpu_rd_user->collector.last_stored_value + cg->st_cpu_rd_system->collector.last_stored_value;
+            max_cpu = MAX(max_cpu, cpu);
+        }
+
+        double ram = rrddim_get_last_stored_value(cg->st_mem_rd_ram, &max_ram, 1.0);
+
+        rd = cg->st_throttle_io_rd_read ? cg->st_throttle_io_rd_read : cg->st_io_rd_read;
+        double disk_io_read = rrddim_get_last_stored_value(rd, &max_disk_io_read, 1024.0);
+        rd = cg->st_throttle_io_rd_written ? cg->st_throttle_io_rd_written : cg->st_io_rd_written;
+        double disk_io_written = rrddim_get_last_stored_value(rd, &max_disk_io_written, 1024.0);
+
+        buffer_json_add_array_item_double(wb, pids_current);
+        buffer_json_add_array_item_double(wb, cpu);
+        buffer_json_add_array_item_double(wb, ram);
+        buffer_json_add_array_item_double(wb, disk_io_read);
+        buffer_json_add_array_item_double(wb, disk_io_written);
+
+        buffer_json_array_close(wb);
+    }
+
+    uv_mutex_unlock(&cgroup_root_mutex);
+
+    buffer_json_array_close(wb); // data
+    buffer_json_member_add_object(wb, "columns");
+    {
+        size_t field_id = 0;
+
+        // Node
+        buffer_rrdf_table_add_field(wb, field_id++, "Name", "Systemd Service Name",
+                RRDF_FIELD_TYPE_STRING, RRDF_FIELD_VISUAL_VALUE, RRDF_FIELD_TRANSFORM_NONE,
+                0, NULL, NAN, RRDF_FIELD_SORT_ASCENDING, NULL,
+                RRDF_FIELD_SUMMARY_COUNT, RRDF_FIELD_FILTER_MULTISELECT,
+                RRDF_FIELD_OPTS_VISIBLE | RRDF_FIELD_OPTS_UNIQUE_KEY | RRDF_FIELD_OPTS_STICKY | RRDF_FIELD_OPTS_FULL_WIDTH,
+                NULL);
+
+        // PIDs
+        buffer_rrdf_table_add_field(wb, field_id++, "PIDs", "Number of Processes Currently in the CGROUP",
+                RRDF_FIELD_TYPE_INTEGER, RRDF_FIELD_VISUAL_VALUE, RRDF_FIELD_TRANSFORM_NUMBER,
+                0, "pids", max_pids, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // CPU
+        buffer_rrdf_table_add_field(wb, field_id++, "CPU", "CPU Usage",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "%", max_cpu, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // RAM
+        buffer_rrdf_table_add_field(wb, field_id++, "RAM", "RAM Usage",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "MiB", max_ram, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // Disk IO Reads
+        buffer_rrdf_table_add_field(wb, field_id++, "Reads", "Disk Read Data",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "MiB", max_disk_io_read, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+
+        // Disk IO Writes
+        buffer_rrdf_table_add_field(wb, field_id++, "Writes", "Disk Written Data",
+                RRDF_FIELD_TYPE_BAR_WITH_INTEGER, RRDF_FIELD_VISUAL_BAR, RRDF_FIELD_TRANSFORM_NUMBER,
+                2, "MiB", max_disk_io_written, RRDF_FIELD_SORT_DESCENDING, NULL,
+                RRDF_FIELD_SUMMARY_SUM, RRDF_FIELD_FILTER_NONE,
+                RRDF_FIELD_OPTS_VISIBLE,
+                NULL);
+    }
+
+    buffer_json_object_close(wb); // columns
+    buffer_json_member_add_string(wb, "default_sort_column", "CPU");
+
+    buffer_json_member_add_object(wb, "charts");
+    {
+        buffer_json_member_add_object(wb, "CPU");
+        {
+            buffer_json_member_add_string(wb, "name", "CPU");
+            buffer_json_member_add_string(wb, "type", "stacked-bar");
+            buffer_json_member_add_array(wb, "columns");
+            {
+                buffer_json_add_array_item_string(wb, "CPU");
+            }
+            buffer_json_array_close(wb);
+        }
+        buffer_json_object_close(wb);
+
+        buffer_json_member_add_object(wb, "Memory");
+        {
+            buffer_json_member_add_string(wb, "name", "Memory");
+            buffer_json_member_add_string(wb, "type", "stacked-bar");
+            buffer_json_member_add_array(wb, "columns");
+            {
+                buffer_json_add_array_item_string(wb, "RAM");
+            }
+            buffer_json_array_close(wb);
+        }
+        buffer_json_object_close(wb);
+    }
+    buffer_json_object_close(wb); // charts
+
+    buffer_json_member_add_array(wb, "default_charts");
+    {
+        buffer_json_add_array_item_array(wb);
+        buffer_json_add_array_item_string(wb, "CPU");
+        buffer_json_add_array_item_string(wb, "Name");
+        buffer_json_array_close(wb);
+
+        buffer_json_add_array_item_array(wb);
+        buffer_json_add_array_item_string(wb, "Memory");
+        buffer_json_add_array_item_string(wb, "Name");
+        buffer_json_array_close(wb);
+    }
+    buffer_json_array_close(wb);
+
+    buffer_json_member_add_time_t(wb, "expires", now_realtime_sec() + 1);
+    buffer_json_finalize(wb);
+
+    int response = HTTP_RESP_OK;
+    if(is_cancelled_cb && is_cancelled_cb(is_cancelled_cb_data)) {
+        buffer_flush(wb);
+        response = HTTP_RESP_CLIENT_CLOSED_REQUEST;
+    }
+
+    if(result_cb)
+        result_cb(wb, response, result_cb_data);
+
+    return response;
+}