Dump Internals / Signal
When the service is running we can export metrics to see the overall status of the data flow of the service. But there are other use cases where we would like to know the current status of the internals of the service, specifically to answer questions like what's the current status of the internal buffers ? , the Dump Internals feature is the answer.
Fluent Bit v1.4 introduces the Dump Internals feature that can be triggered easily from the command line triggering the
Run the following
killcommand to signal Fluent Bit:
kill -CONT `pidof fluent-bit`
pidofaims to lookup the Process ID of Fluent Bit. You can replace the
Fluent Bit will dump the following information to the standard output interface (stdout):
[engine] caught signal (SIGCONT)
[2020/03/23 17:39:02] Fluent Bit Dump
===== Input =====
│ └─ overlimit : no
│ ├─ mem size : 60.8M (63752145 bytes)
│ └─ mem limit : 61.0M (64000000 bytes)
│ ├─ total tasks : 92
│ ├─ new : 0
│ ├─ running : 92
│ └─ size : 171.1M (179391504 bytes)
└─ total chunks : 92
├─ up chunks : 35
├─ down chunks: 57
└─ busy chunks: 92
├─ size : 60.8M (63752145 bytes)
└─ size err: 0
===== Storage Layer =====
total chunks : 92
├─ mem chunks : 0
└─ fs chunks : 92
├─ up : 35
└─ down : 57
The dump provides insights for every input instance configured.
Overall ingestion status of the plugin.
When an input plugin ingest data into the engine, a Chunk is created. A Chunk can contains multiple records. Upon flush time, the engine creates a Task that contains the routes for the Chunk associated in question.
The Task dump describes the tasks associated to the input plugin:
The Chunks dump tells more details about all the chunks that the input plugin has generated and are still being processed.
Depending of the buffering strategy and limits imposed by configuration, some Chunks might be
up(in memory) or
Fluent Bit relies on a custom storage layer interface designed for hybrid buffering. The
Storage Layerentry contains a total summary of Chunks registered by Fluent Bit: