external_cache

02/11/2024 Contributors

This table provides performance metrics and configuration characteristics for a given WAFL External Cache type, such as Flash Cache or the Predictive Cache Statistics simulator. High-level cache behavior can be monitored using these statistics.

Classic Object: ext_cache_obj

Table Row IDs

ID Format	Aggregation Type	Comment
{instance_name}	(not applicable)	This represents the construction of the row ID field, which is a single unique string that identifies a row.

ID Format

Aggregation Type

Comment

{instance_name}

(not applicable)

This represents the construction of the row ID field, which is a single unique string that identifies a row.

Properties

This section describes the mapping between classic (ONTAPI) string counter names and REST property names.

Classic String Counter	REST Property	Description
node_name	node.name	System node name

Classic String Counter

REST Property

Description

node_name

node.name

System node name

Counters

This section describes the mapping between classic (ONTAPI) numeric counter names and REST counter names.

Classic Numeric Counter	REST Counter	Description
usage	usage	Percentage of blocks in external cache currently containing valid data
accesses	accesses	External cache accesses per second
disk_reads_replaced	disk_reads_replaced	Estimated number of disk reads per second replaced by cache
hit	hit.total	Number of WAFL buffers served off the external cache
hit_normal_lev0	hit.normal_level_zero	Number of normal level 0 WAFL buffers served off the external cache
hit_metadata_file	hit.metadata_file	Number of metadata file buffers served off the external cache
hit_directory	hit.directory	Number of directory buffers served off the external cache
hit_indirect	hit.indirect	Number of indirect file buffers served off the external cache
miss	miss.total	External cache misses
miss_normal_lev0	miss.normal_level_zero	External cache misses accessing normal level 0 buffers
miss_metadata_file	miss.metadata_file	External cache misses accessing metadata file buffers
miss_directory	miss.directory	External cache misses accessing directory buffers
miss_indirect	miss.indirect	External cache misses accessing indirect file buffers
hit_percent	hit.percent	External cache hit rate
inserts	inserts	Number of WAFL buffers inserted into the external cache
evicts	evicts	Number of blocks evicted from the external cache to make room for new blocks
invalidates	invalidates	Number of blocks invalidated in the external cache

Classic Numeric Counter

REST Counter

Description

usage

Percentage of blocks in external cache currently containing valid data

accesses

External cache accesses per second

disk_reads_replaced

Estimated number of disk reads per second replaced by cache

hit

hit.total

Number of WAFL buffers served off the external cache

hit_normal_lev0

hit.normal_level_zero

Number of normal level 0 WAFL buffers served off the external cache

hit_metadata_file

hit.metadata_file

Number of metadata file buffers served off the external cache

hit_directory

hit.directory

Number of directory buffers served off the external cache

hit_indirect

hit.indirect

Number of indirect file buffers served off the external cache

miss

miss.total

External cache misses

miss_normal_lev0

miss.normal_level_zero

External cache misses accessing normal level 0 buffers

miss_metadata_file

miss.metadata_file

External cache misses accessing metadata file buffers

miss_directory

miss.directory

External cache misses accessing directory buffers

miss_indirect

miss.indirect

External cache misses accessing indirect file buffers

hit_percent

hit.percent

External cache hit rate

inserts

Number of WAFL buffers inserted into the external cache

evicts

Number of blocks evicted from the external cache to make room for new blocks

invalidates

Number of blocks invalidated in the external cache

Property/Counter Content Changes

This section describes any output value differences between the classic (ONTAPI) string counter and the respective REST property. It also describes array label name changes between classic array counters and respective REST array counters.

Table Aliases

This section describes aliases for aggregated tables.