K8S resource allocations details.

kubectl-view-resources

#!/usr/bin/env bash
#:set expandtab tabstop=4 shiftwidth=4 autoindent
# Prerequisites:
#   brew install coreutils # for numfmt
#   brew install jq
#   brew install bash
set -euo pipefail

to1() {
    local n=${1:-0}
    if [[ "$n" == *m ]]; then
        <<<"scale=3; ${n::-1} / 1000" bc
    else
        <<<"$n" numfmt --from=auto
    fi
}

to1_sum() {
    local n
    local s=0
    while IFS= read -r n; do
        s=$(<<<"scale=3; $s + $(to1 $n)" bc)
    done
    echo -n "$s"
}

toh() {
    <<<"${1:-0}" numfmt --to=iec-i
}

node_all_resources() {
    local node="$1"
    local key val
    local pods_json node_json remained
    declare -A capacity allocatable requests

    node_json=$(kubectl get no -ojson "$node")
    pods_json=$(kubectl get po --all-namespaces --field-selector spec.nodeName="$node" -ojson)
    requests[pods]=$(kubectl get po --all-namespaces --field-selector spec.nodeName="$node" --no-headers | wc -l)

    while read -r key val; do
        capacity[$key]=$(to1 "$val")
    done < <(<<<"$node_json" jq '.status.capacity' | sed '1d;$d;s/[,:"]//g')

    while read -r key val; do
        allocatable[$key]=$(to1 "$val")
        [[ "$key" == "pods" ]] && continue
        requests[$key]=$(<<<"$pods_json" jq -r ".items[].spec.containers[].resources.requests.\"$key\" | values" | to1_sum)
    done < <(<<<"$node_json" jq '.status.allocatable' | sed '1d;$d;s/[,:"]//g')

    {
        echo "Node Capacity Allocatable Requested Remained"
        for key in "${!allocatable[@]}"; do
            remained=$((${allocatable[$key]} - ${requests[$key]}))
            case "$key" in
            "cpu" | "pods")
                echo "$key ${capacity[$key]} ${allocatable[$key]} ${requests[$key]} $remained"
                ;;
            *)
                echo "$key $(toh ${capacity[$key]}) $(toh ${allocatable[$key]}) $(toh ${requests[$key]}) $(toh $remained)"
                ;;
            esac

        done
    } | column -t | { read -r;echo "$REPLY";sort; }
}

node_single_resource() {
    local node="$1"
    local resource="$2"
    local requests_total=0
    local key val remained
    local namespace pod container capacity allocatable
    declare -A requests

   while read -r namespace pod container val; do
        [[ "$val" == "null" || "$val" == 0 ]] && continue
        requests["$namespace $pod $container"]="$val"
        requests_total=$((requests_total + $(to1 "$val")))
   done < <(kubectl get po --all-namespaces --field-selector spec.nodeName="$node" -ojson \
        | jq -c ".items[] as \$p | \$p.spec.containers[] as \$c
        | [\$p.metadata.namespace,\$p.metadata.name,\$c.name,\$c.resources.requests.\"$resource\"]" \
        | sed 's/[]["]//g;s/,/ /g')
    {
        echo "Namespace Pod Container Requests"
        for key in "${!requests[@]}"; do
            echo "$key ${requests[$key]}"
        done
    } | column -t | { read -r; echo "$REPLY"; sort -k4hr,4 -k1,1 -k2,2 -k3,3; }

    read -r capacity allocatable < <(kubectl get no "$node" -ojson \
        | jq -rc "[.status.capacity.\"$resource\",.status.allocatable.\"$resource\"]" \
        | sed 's/[]["]//g;s/,/ /g')
    remained=$(to1 "$allocatable")
    remained=$((remained - requests_total))
    remained=$(toh "$remained")
    requests_total=$(toh "$requests_total")
    echo
    echo "Capacity:$capacity Allocatable:$allocatable Requested:$requests_total Remained:$remained"
}

all_node_single_resource() {
    local cnt=0
    local resource="$1"
    local val node remained cap alloc
    declare -A capacity allocatable requests

    local f_pipe=$(mktemp -u)
    mkfifo -m 600 "$f_pipe"
    exec 3<>"$f_pipe"
    rm -f "$f_pipe"

    while read -r node cap alloc; do
        [[ "$cap" == "null" ]] && continue
        capacity[$node]=$(to1 "$cap")
        allocatable[$node]=$(to1 "$alloc")
        {
            echo $node $(kubectl get po --all-namespaces --field-selector spec.nodeName="$node" -ojson \
                | jq -r ".items[].spec.containers[].resources.requests.\"$resource\" | values" \
                | to1_sum)
        } >&3 &
        cnt=$((cnt+1))
    done < <(kubectl get no -ojson \
        | jq -c ".items[]|[.metadata.name,.status.capacity.\"$resource\",.status.allocatable.\"$resource\"]" \
        | sed 's/[]["]//g;s/,/ /g')

    while [[ "$cnt" -gt 0 ]]; do
        read -ru3 node val
        requests[$node]="$val"
        cnt=$((cnt-1))
    done
    exec 3<&- 3>&-

    {
        echo "Node Capacity Allocatable Requested Remained"
        for node in "${!requests[@]}"; do
            if [[ "${capacity[$node]}" -eq 0 && "${requests[$node]:-0}" -eq 0 ]]; then
                continue
            fi
            remained=$((${allocatable[$node]} - ${requests[$node]:-0}))
            case "$resource" in
            "cpu" | "pods")
                echo "$node ${capacity[$node]} ${allocatable[$node]} ${requests[$node]} $remained"
                ;;
            *)
                echo "$node $(toh ${capacity[$node]}) $(toh ${allocatable[$node]}) $(toh ${requests[$node]}) $(toh $remained)"
                ;;
            esac
        done
    } | column -t | { read -r;echo "$REPLY"; sort -k5hr,5 -k1,1; }
}

main() {
    local opt node resource

    while getopts "n:r:" opt; do
        case $opt in
        "n")
            node="$OPTARG"
            ;;
        "r")
            resource="$OPTARG"
            ;;
        esac
    done

    if [[ "${node-}" ]]; then
        if [[ "${resource-}" ]]; then
            node_single_resource "$node" "$resource"
        else
            node_all_resources "$node"
        fi
    elif [[ "${resource-}" ]]; then
        all_node_single_resource "$resource"
    else
        echo "Usage: $0 -n <node> -r <resource> # show all containers requesting <resource> on <node>"
        echo "Usage: $0 -r <resource>           # show <resource> on all nodes"
        echo "Usage: $0 -n <node>               # show all types of resources <node>"
        exit 1
    fi
}

main "$@"

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