90 lines
2.3 KiB
Markdown
90 lines
2.3 KiB
Markdown
|
# Telegraf plugin: bcache
|
||
|
|
||
|
Get bcache stat from stats_total directory and dirty_data file.
|
||
|
|
||
|
# Measurements
|
||
|
|
||
|
Meta:
|
||
|
|
||
|
- tags: `backing_dev=dev bcache_dev=dev`
|
||
|
|
||
|
Measurement names:
|
||
|
|
||
|
- dirty_data
|
||
|
- bypassed
|
||
|
- cache_bypass_hits
|
||
|
- cache_bypass_misses
|
||
|
- cache_hit_ratio
|
||
|
- cache_hits
|
||
|
- cache_miss_collisions
|
||
|
- cache_misses
|
||
|
- cache_readaheads
|
||
|
|
||
|
### Description
|
||
|
|
||
|
```
|
||
|
dirty_data
|
||
|
Amount of dirty data for this backing device in the cache. Continuously
|
||
|
updated unlike the cache set's version, but may be slightly off.
|
||
|
|
||
|
bypassed
|
||
|
Amount of IO (both reads and writes) that has bypassed the cache
|
||
|
|
||
|
|
||
|
cache_bypass_hits
|
||
|
cache_bypass_misses
|
||
|
Hits and misses for IO that is intended to skip the cache are still counted,
|
||
|
but broken out here.
|
||
|
|
||
|
cache_hits
|
||
|
cache_misses
|
||
|
cache_hit_ratio
|
||
|
Hits and misses are counted per individual IO as bcache sees them; a
|
||
|
partial hit is counted as a miss.
|
||
|
|
||
|
cache_miss_collisions
|
||
|
Counts instances where data was going to be inserted into the cache from a
|
||
|
cache miss, but raced with a write and data was already present (usually 0
|
||
|
since the synchronization for cache misses was rewritten)
|
||
|
|
||
|
cache_readaheads
|
||
|
Count of times readahead occurred.
|
||
|
```
|
||
|
|
||
|
# Example output
|
||
|
|
||
|
Using this configuration:
|
||
|
|
||
|
```
|
||
|
[bcache]
|
||
|
# Bcache sets path
|
||
|
# If not specified, then default is:
|
||
|
# bcachePath = "/sys/fs/bcache"
|
||
|
#
|
||
|
# By default, telegraf gather stats for all bcache devices
|
||
|
# Setting devices will restrict the stats to the specified
|
||
|
# bcache devices.
|
||
|
# bcacheDevs = ["bcache0", ...]
|
||
|
```
|
||
|
|
||
|
When run with:
|
||
|
|
||
|
```
|
||
|
./telegraf -config telegraf.conf -filter bcache -test
|
||
|
```
|
||
|
|
||
|
It produces:
|
||
|
|
||
|
```
|
||
|
* Plugin: bcache, Collection 1
|
||
|
> [backing_dev="md10" bcache_dev="bcache0"] bcache_dirty_data value=11639194
|
||
|
> [backing_dev="md10" bcache_dev="bcache0"] bcache_bypassed value=5167704440832
|
||
|
> [backing_dev="md10" bcache_dev="bcache0"] bcache_cache_bypass_hits value=146270986
|
||
|
> [backing_dev="md10" bcache_dev="bcache0"] bcache_cache_bypass_misses value=0
|
||
|
> [backing_dev="md10" bcache_dev="bcache0"] bcache_cache_hit_ratio value=90
|
||
|
> [backing_dev="md10" bcache_dev="bcache0"] bcache_cache_hits value=511941651
|
||
|
> [backing_dev="md10" bcache_dev="bcache0"] bcache_cache_miss_collisions value=157678
|
||
|
> [backing_dev="md10" bcache_dev="bcache0"] bcache_cache_misses value=50647396
|
||
|
> [backing_dev="md10" bcache_dev="bcache0"] bcache_cache_readaheads value=0
|
||
|
```
|