dmcache

Device Mapper Cache Input Plugin

This plugin provide a native collection for dmsetup based statistics for dm-cache.

[!NOTE] This plugin requires super-user permissions! Please make sure, Telegraf is able to run sudo /sbin/dmsetup status --target cache without requiring a password.

⭐ Telegraf v1.3.0 🏷️ system 💻 linux

Global configuration options

Plugins support additional global and plugin configuration settings for tasks such as modifying metrics, tags, and fields, creating aliases, and configuring plugin ordering. See CONFIGURATION.md for more details.

Configuration

# Provide a native collection for dmsetup based statistics for dm-cache
# This plugin ONLY supports Linux
[[inputs.dmcache]]
  ## Whether to report per-device stats or not
  per_device = true

Metrics

• dmcache
  • length
  • target
  • metadata_blocksize
  • metadata_used
  • metadata_total
  • cache_blocksize
  • cache_used
  • cache_total
  • read_hits
  • read_misses
  • write_hits
  • write_misses
  • demotions
  • promotions
  • dirty

Tags

• All measurements have the following tags:
  • device

Example Output

dmcache,device=example cache_blocksize=0i,read_hits=995134034411520i,read_misses=916807089127424i,write_hits=195107267543040i,metadata_used=12861440i,write_misses=563725346013184i,promotions=3265223720960i,dirty=0i,metadata_blocksize=0i,cache_used=1099511627776ii,cache_total=0i,length=0i,metadata_total=1073741824i,demotions=3265223720960i 1491482035000000000