LVM 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 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

Macros used

There are no macros links in this template.

Template links

There are no template links in this template.

Discovery rules

There are no discovery rules in this template.

Items collected

Name	Description	Type	Key and additional info
LVM meta cache usage	<p>-</p>	Calculated	lvmcache.metausage<p>Update: 3m</p>
LVM data cache usage	<p>-</p>	Calculated	lvmcache.usage<p>Update: 3m</p>
used_metadata_blocks	<p>-</p>	Dependent item	lvmcache.used_metadata_blocks<p>Update: 0</p>
demotions	<p>-</p>	Dependent item	lvmcache.demotions<p>Update: 0</p>
read_hits	<p>-</p>	Dependent item	lvmcache.read_hits<p>Update: 0</p>
write_misses	<p>-</p>	Dependent item	lvmcache.write_misses<p>Update: 0</p>
lvm raw data	<p>-</p>	Zabbix agent	lvmcache.raw<p>Update: 3m</p>
dirty	<p>-</p>	Dependent item	lvmcache.dirty<p>Update: 0</p>
write_hits	<p>-</p>	Dependent item	lvmcache.write_hits<p>Update: 0</p>
total_metadata_blocks	<p>-</p>	Dependent item	lvmcache.total_metadata_blocks<p>Update: 0</p>
promotions	<p>-</p>	Dependent item	lvmcache.promotions<p>Update: 0</p>
used_cache_blocks	<p>-</p>	Dependent item	lvmcache.used_cache_blocks<p>Update: 0</p>
total_cache_blocks	<p>-</p>	Dependent item	lvmcache.total_cache_blocks<p>Update: 0</p>

Triggers

There are no triggers in this template.

LVM 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 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

Macros used

There are no macros links in this template.

Template links

There are no template links in this template.

Discovery rules

There are no discovery rules in this template.

Items collected

Name	Description	Type	Key and additional info
demotions	<p>-</p>	Dependent item	lvmcache.demotions<p>Update: 0</p>
used_metadata_blocks	<p>-</p>	Dependent item	lvmcache.used_metadata_blocks<p>Update: 0</p>
write_misses	<p>-</p>	Dependent item	lvmcache.write_misses<p>Update: 0</p>
dirty	<p>-</p>	Dependent item	lvmcache.dirty<p>Update: 0</p>
LVM data cache usage	<p>-</p>	Calculated	lvmcache.usage<p>Update: 3m</p>
LVM meta cache usage	<p>-</p>	Calculated	lvmcache.metausage<p>Update: 3m</p>
used_cache_blocks	<p>-</p>	Dependent item	lvmcache.used_cache_blocks<p>Update: 0</p>
total_metadata_blocks	<p>-</p>	Dependent item	lvmcache.total_metadata_blocks<p>Update: 0</p>
total_cache_blocks	<p>-</p>	Dependent item	lvmcache.total_cache_blocks<p>Update: 0</p>
read_hits	<p>-</p>	Dependent item	lvmcache.read_hits<p>Update: 0</p>
promotions	<p>-</p>	Dependent item	lvmcache.promotions<p>Update: 0</p>
lvm raw data	<p>-</p>	Zabbix agent	lvmcache.raw<p>Update: 3m</p>
write_hits	<p>-</p>	Dependent item	lvmcache.write_hits<p>Update: 0</p>

Triggers

There are no triggers in this template.

LVM 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 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

Macros used

There are no macros links in this template.

Template links

There are no template links in this template.

Discovery rules

There are no discovery rules in this template.

Items collected

Name	Description	Type	Key and additional info
demotions	<p>-</p>	Dependent item	lvmcache.demotions<p>Update: 0</p>
used_metadata_blocks	<p>-</p>	Dependent item	lvmcache.used_metadata_blocks<p>Update: 0</p>
write_misses	<p>-</p>	Dependent item	lvmcache.write_misses<p>Update: 0</p>
dirty	<p>-</p>	Dependent item	lvmcache.dirty<p>Update: 0</p>
LVM data cache usage	<p>-</p>	Calculated	lvmcache.usage<p>Update: 3m</p>
LVM meta cache usage	<p>-</p>	Calculated	lvmcache.metausage<p>Update: 3m</p>
used_cache_blocks	<p>-</p>	Dependent item	lvmcache.used_cache_blocks<p>Update: 0</p>
total_metadata_blocks	<p>-</p>	Dependent item	lvmcache.total_metadata_blocks<p>Update: 0</p>
total_cache_blocks	<p>-</p>	Dependent item	lvmcache.total_cache_blocks<p>Update: 0</p>
read_hits	<p>-</p>	Dependent item	lvmcache.read_hits<p>Update: 0</p>
promotions	<p>-</p>	Dependent item	lvmcache.promotions<p>Update: 0</p>
lvm raw data	<p>-</p>	Zabbix agent	lvmcache.raw<p>Update: 3m</p>
write_hits	<p>-</p>	Dependent item	lvmcache.write_hits<p>Update: 0</p>

Triggers

There are no triggers in this template.