Protocol: SMB Operations

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This statistic shows SMB operations/sec (SMB IOPS) requested by clients to the appliance. Various useful breakdowns are available: to show the client, filename and latency of the SMB I/O.

Example

See Protocol: NFSv[2-4] Operations for an example of a similar statistic with similar breakdowns.

When to Check SMB Operations

SMB operations/sec can be used as an indication of SMB load, and can be viewed on the dashboard.

Use the latency breakdown when investigating SMB performance issues, especially to quantify the magnitude of the issue. This measures the I/O latency component for which the appliance is responsible for, and displays it as a heat map so that the overall latency pattern can be seen, along with outliers. If the SMB latency is high, drill down further on latency to identify the type of operation and filename for the high latency, and, check other statistics for both CPU and Disk load to investigate why the appliance is slow to respond; if latency is low, the appliance is performing quickly, and any performance issues experienced on the client are more likely to be caused by other factors in the environment: such as the network infrastructure, and CPU load on the client itself.

The best way to improve performance is to eliminate unnecessary work, which may be identified through the client and filename breakdowns, and the filename hierarchy view. Client and especially filename breakdowns can be very expensive in terms of storage and execution overhead. Therefore, it is not recommended to permanently enable these breakdowns on a busy production appliance.

SMB Operations Breakdowns

Table 36 Breakdowns of SMB Operations

Breakdown	Description
type of operation	SMB operation type (read/write/readX/writeX/...)
client	Remote hostname or IP address of the SMB client.
filename	Filename for the SMB I/O, if known and cached by the appliance. If the filename is not known it is reported as "<unknown>".
share	The share for this SMB I/O.
project	The project for this SMB I/O.
latency	A heat map showing the latency of SMB I/O, as measured from when the SMB request arrived on the appliance from the network, to when the response is sent; this latency includes the time to process the SMB request, and to perform any disk I/O.
size	A heat map showing the distribution of SMB I/O sizes.
offset	A heat map showing the file offset of SMB I/O. This can be used to identify random or sequential SMB IOPS. Use the Disk I/O operations statistic to check whether random SMB IOPS maps to random Disk IOPS after the filesystem and RAID configuration has been applied.

These breakdowns can be combined to produce powerful statistics. For example:

"Protocol: SMB operations per second of type read broken down by latency" (to examine latency for reads only)
"Protocol: SMB operations per second for file '/export/fs4/10ga' broken down by offset" (to examine file access pattern for a particular file)
"Protocol: SMB operations per second for client 'phobos.sf.fishpong.com' broken down by filename" (to view which files a particular client is accessing)

Further Analysis

See Network: Device Bytes for a measure of network throughput caused by the SMB activity; Cache: ARC Accesses to learn how well an SMB read workload is returning from cache; and Disk: I/O Operations for the back-end disk I/O caused.