added script to check how many pgs per osd per pool per ceph cluster …

…per mike mcphee

pg_info.sh

@@ -0,0 +1,158 @@
+#!/usr/bin/env bash
+#
+# pg_per_osd_ec_replicated.sh
+#
+# 1) Gets total OSD count from the cluster.
+# 2) Lists each pool, checks if it's replicated or erasure-coded.
+#    - For replicated pools, uses (pg_num * size) / OSD_COUNT.
+#    - For EC pools, retrieves (k+m) from the pool's erasure-code profile,
+#      then uses (pg_num * (k + m)) / OSD_COUNT.
+# 3) Prints the "PG per OSD" for each pool.
+#
+# Requirements:
+#   - ceph CLI
+#   - jq
+
+set -e
+
+# ------------------------------------------------------------------------------
+# 1) Get total number of OSDs
+# ------------------------------------------------------------------------------
+OSD_COUNT=$(ceph osd stat --format json | jq -r '.num_osds')
+if [[ -z "$OSD_COUNT" || "$OSD_COUNT" -le 0 ]]; then
+  echo "ERROR: Could not retrieve a valid OSD count!"
+  exit 1
+fi
+
+# ------------------------------------------------------------------------------
+# 2) Get pool details (type, size, pg_num, erasure_code_profile, etc.)
+#    "ceph osd pool ls detail --format json" returns an array of pools.
+# ------------------------------------------------------------------------------
+POOL_DETAILS=$(ceph osd pool ls detail --format json)
+if [[ -z "$POOL_DETAILS" ]]; then
+  echo "ERROR: Could not retrieve pool details!"
+  exit 1
+fi
+
+# We'll parse .type to see if it's replicated or ec.
+# For Ceph versions:
+#   type = 1 => replicated
+#   type = 3 => erasure-coded
+#
+# (There might be older or alternate representations, but this is standard.)
+#
+
+# ------------------------------------------------------------------------------
+# Function to retrieve and cache 'k' and 'm' for a given EC profile
+# ------------------------------------------------------------------------------
+declare -A EC_K
+declare -A EC_M
+
+get_ec_params() {
+  local profile="$1"
+
+  # If we've already cached this profile, skip the CLI call
+  if [[ -n "${EC_K[$profile]}" && -n "${EC_M[$profile]}" ]]; then
+    return
+  fi
+
+  # Retrieve the profile as JSON, e.g.:
+  #   {
+  #     "k": "2",
+  #     "m": "1",
+  #     ...
+  #   }
+  local profile_json
+  profile_json=$(ceph osd erasure-code-profile get "$profile" --format json)
+
+  # Extract k, m
+  local k_val m_val
+  # shellcheck disable=SC2086
+  read -r k_val m_val < <(echo "$profile_json" | jq -r '[.k, .m] | @sh' | xargs echo)
+
+  # Cache them
+  EC_K["$profile"]="$k_val"
+  EC_M["$profile"]="$m_val"
+}
+
+# ------------------------------------------------------------------------------
+# 3) Loop over each pool and compute PG per OSD
+# ------------------------------------------------------------------------------
+echo "Total OSDs in cluster: $OSD_COUNT"
+echo "=========================================================="
+
+# We'll use jq to extract the needed fields and iterate:
+echo "$POOL_DETAILS" | jq -r '
+  .[] |
+  {
+    name: .pool_name,
+    pg_num: .pg_num,
+    type: .type,
+    size: (if .type == 1 then .size else null end),
+    ec_profile: (if .type == 3 then .erasure_code_profile else null end)
+  } |
+  "\(.name)\t\(.pg_num)\t\(.type)\t\(.size)\t\(.ec_profile)"
+' | while IFS=$'\t' read -r POOL_NAME POOL_PG POOL_TYPE POOL_SIZE EC_PROFILE; do
+
+  # POOL_TYPE=1 => replicated, POOL_TYPE=3 => EC
+  if [[ "$POOL_TYPE" -eq 1 ]]; then
+    # Replicated pool
+    # Formula: PG per OSD = (pg_num * size) / OSD_COUNT
+    if [[ -z "$POOL_SIZE" ]]; then
+      echo "ERROR: Replicated pool '$POOL_NAME' has no 'size' field!"
+      continue
+    fi
+
+    PG_PER_OSD=$(awk -v pg="$POOL_PG" -v sz="$POOL_SIZE" -v osd="$OSD_COUNT" '
+      BEGIN {
+        val = (pg * sz) / osd;
+        printf "%.2f", val;
+      }'
+    )
+    echo -e "Pool Name: \e[31m$POOL_NAME\e[0m"
+    echo "  Type                : Replicated"
+    echo "  Replication size    : $POOL_SIZE"
+    echo "  Current PG count    : $POOL_PG"
+#    echo "  PG per OSD (formula): ($POOL_PG * $POOL_SIZE) / $OSD_COUNT = $PG_PER_OSD"
+    echo "  PG per OSD          : $PG_PER_OSD"
+    echo
+
+  elif [[ "$POOL_TYPE" -eq 3 ]]; then
+    # Erasure-coded pool
+    # 1) Retrieve the EC profile => get k, m
+    if [[ -z "$EC_PROFILE" ]]; then
+      echo "ERROR: EC pool '$POOL_NAME' has no 'erasure_code_profile'!"
+      continue
+    fi
+
+    get_ec_params "$EC_PROFILE"
+    K_VAL="${EC_K[$EC_PROFILE]}"
+    M_VAL="${EC_M[$EC_PROFILE]}"
+    if [[ -z "$K_VAL" || -z "$M_VAL" ]]; then
+      echo "ERROR: Could not determine k and m for profile '$EC_PROFILE'!"
+      continue
+    fi
+
+    # Formula: PG per OSD = (pg_num * (k + m)) / OSD_COUNT
+    PG_PER_OSD=$(awk -v pg="$POOL_PG" -v k="$K_VAL" -v m="$M_VAL" -v osd="$OSD_COUNT" '
+      BEGIN {
+        val = (pg * (k + m)) / osd;
+        printf "%.2f", val;
+      }'
+    )
+
+    echo -e "Pool Name: \e[31m$POOL_NAME\e[0m"
+    echo "  Type                : Erasure-coded"
+#    echo "  EC profile          : $EC_PROFILE"
+    echo "  k + m               : $K_VAL + $M_VAL"
+    echo "  Current PG count    : $POOL_PG"
+#    echo "  PG per OSD (formula): ($POOL_PG * ($K_VAL + $M_VAL)) / $OSD_COUNT = $PG_PER_OSD"
+    echo "  PG per OSD          : $PG_PER_OSD"
+    echo
+  else
+    echo "Pool Name: $POOL_NAME"
+    echo "  Unrecognized type: $POOL_TYPE (not 1, not 3). Skipping."
+    echo
+  fi
+
+done