# tt_fabric_tx_max_bandwidth_megabytes_per_second

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## Name

### Prometheus Metric Name

```
tt_fabric_tx_max_bandwidth_megabytes_per_second
```

### Metric Path (tt-telemetry)

Schema:

```
{hostname}/tray{tray}/chip{chip}/channel{channel}/fabric/tt_fabric_tx_max_bandwidth_megabytes_per_second
```

Example path:

```
bh-glx-c09u02/tray1/chip2/channel0/fabric/tt_fabric_tx_max_bandwidth_megabytes_per_second
```

## Description

The maximum transmit bandwidth observed on a specific fabric Ethernet channel in megabytes per second (MB/s). This tracks the peak active transmit bandwidth over a moving window of 10 samples, providing a running maximum. The value resets on counter wraparound or sampling gaps but is preserved during periods of no activity. This metric is available on Wormhole B0 and Blackhole devices.

Note: Fabric metrics are only updated by fabric firmware when workloads are run with fabric telemetry explicitly enabled. For example, by setting the environment variable `TT_METAL_FABRIC_TELEMETRY` to `1`.

## Values

**Type:** Floating Point

**Units:** Megabytes per second (MB/s)

**Allowable values:**
A non-negative floating-point number representing the peak transmit bandwidth observed over the moving window.

## Prometheus Labels

|Label Name|Value|
|---|---|
|hostname|The host from which the metric was collected.|
|hall|The datacenter hall where the host is located. Sourced from the Factory System Descriptor (FSD).|
|aisle|The datacenter aisle where the host is located. Sourced from the Factory System Descriptor (FSD).|
|rack|The rack number where the host is located. Sourced from the Factory System Descriptor (FSD).|
|shelf_u|The shelf U position in the rack where the host is located. Sourced from the Factory System Descriptor (FSD).|
|tray|The tray (UBB) that the device is located on.|
|chip|The ASIC location within the tray.|
|channel|The Ethernet channel number on the chip.|
|port_type|The physical port type (e.g., QSFP, backplane). Present when topology information is available.|
|port_id|The physical port ID. Present when topology information is available.|
|remote_hostname|The hostname of the remote endpoint. Present when remote endpoint information is available.|
|remote_tray|The tray number of the remote endpoint. Present when remote endpoint information is available.|
|remote_chip|The ASIC location of the remote endpoint. Present when remote endpoint information is available.|
|remote_channel|The Ethernet channel of the remote endpoint. Present when remote endpoint information is available.|
|remote_hall|The datacenter hall of the remote endpoint. Present when remote endpoint information is available.|
|remote_aisle|The datacenter aisle of the remote endpoint. Present when remote endpoint information is available.|
|remote_rack|The rack number of the remote endpoint. Present when remote endpoint information is available.|
|remote_shelf_u|The shelf U position of the remote endpoint. Present when remote endpoint information is available.|