5.02021-11-21T22:04:11ZTemplates/Operating SystemsLVM CacheLVM Cache## Description
LVM cache monitoring Details in kernel documentation https://www.kernel.org/doc/Documentation/device-mapper/cache.txt
## Overview
LVM Cache monitoring template.
==============================
allows you to evaluate the efficiency of caching by the built-in dm-cache mechanism.
**What do these values mean?**
------------------------------
Details about monitored values described in Linux Kernel Documentation <https://www.kernel.org/doc/Documentation/device-mapper/cache.txt>
**Usage**
---------
1. Put file lvmcache.conf to /etc/zabbix/zabbix\_agent.d/
2. Put file sudoers\_lvmcache to /etc/sudoers.d/ (you need `sudo` program installed)
3. Put file vmcache to /etc/zabbix/scripts/. Then you can execut this file and test. This script produces JSON output.
4. Import the [`lvmcache_template.xml`](https://github.com/pavlozt/somezabbixtemplates/blob/master/lvmcache/lvmcache_template.xml) into your Zabbix server (click on the `Raw` button to download)
5. Add the template to your host
6. Check if new data arrives at Last Data section and Graphs.
This script assumes that you have **ONLY ONE caching device** and polls the first device. Therefore, it does not require configuration and specifying a device name. Working with disks implies elevated privileges and therefore you need do not forget about sudoers\_zabbix\_lvmcache file.
**Commands for debugging**
--------------------------
* dmsetup status
* /etc/zabbix/scripts/lvmcache
* zabbix\_get -s 192.168.1.1 -k 'lvmcache.raw' (on zabbix server or zabbix proxy)
## Author
pavlozt
Templates/Operating SystemsLVM Cache- demotionsDEPENDENTlvmcache.demotions030dLVM CacheJSONPATH$.demotionsSIMPLE_CHANGElvmcache.raw
- dirtyDEPENDENTlvmcache.dirty030dLVM CacheJSONPATH$.dirtylvmcache.raw
- LVM meta cache usageCALCULATEDlvmcache.metausage3m30dFLOATlast(lvmcache.used_metadata_blocks)/last(lvmcache.total_metadata_blocks)LVM Cache
- promotionsDEPENDENTlvmcache.promotions030dLVM CacheJSONPATH$.promotionsSIMPLE_CHANGElvmcache.raw
- lvm raw datalvmcache.raw3m00TEXTLVM CacheCHECK_JSON_ERROR$.values
- read_hitsDEPENDENTlvmcache.read_hits030dLVM CacheJSONPATH$.read_hitsSIMPLE_CHANGElvmcache.raw
- total_cache_blocksDEPENDENTlvmcache.total_cache_blocks030dLVM CacheJSONPATH$.total_cache_blockslvmcache.raw
- total_metadata_blocksDEPENDENTlvmcache.total_metadata_blocks030dLVM CacheJSONPATH$.total_metadata_blockslvmcache.raw
- LVM data cache usageCALCULATEDlvmcache.usage3m30dFLOATlast(lvmcache.used_cache_blocks)/last(lvmcache.total_cache_blocks)LVM Cache
- used_cache_blocksDEPENDENTlvmcache.used_cache_blocks030dLVM CacheJSONPATH$.used_cache_blockslvmcache.raw
- used_metadata_blocksDEPENDENTlvmcache.used_metadata_blocks030dLVM CacheJSONPATH$.used_metadata_blockslvmcache.raw
- write_hitsDEPENDENTlvmcache.write_hits030dLVM CacheJSONPATH$.write_hitsSIMPLE_CHANGElvmcache.raw
- write_missesDEPENDENTlvmcache.write_misses030dLVM CacheJSONPATH$.write_missesSIMPLE_CHANGElvmcache.raw
LVM Cache efficiency1A7C11- LVM Cachelvmcache.read_hits
1F63100- LVM Cachelvmcache.write_hits
22774A4- LVM Cachelvmcache.write_misses
LVM Cache usageNONOF63100- LVM Cachelvmcache.usage
12774A4- LVM Cachelvmcache.metausage