Protocol: NFSv[2-4] Operations

This statistic shows NFSv[2-4] operations/second (NFS IOPS) requested by clients to Oracle ZFS Storage Appliance. Supported NFS versions are: NFSv2, NFSv3, NFSv4.0, and NFSv4.1. Various breakdowns are available to show the client, filename, and latency of the NFS I/O.

When to Check NFSv[2-4] Operations

NFSv[2-4] operations/sec can be used as an indication of NFS load, and can be viewed on the dashboard.

Use the latency breakdown when investigating NFS performance issues, especially to quantify the magnitude of the issue. This measures the I/O latency component for which Oracle ZFS Storage Appliance is responsible, and displays it as a heat map so that the overall latency pattern can be seen, along with outliers. If the NFS 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 can 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 Oracle ZFS Storage Appliance.

NFSv[2-4] Operations Breakdowns

Table 5-44 Breakdowns of NFS Operations

Breakdown Description

type of operation

NFS operation type (read/write/getattr/setattr/lookup/...).

client

Remote hostname or IP address of the NFS client.

filename

Filename for the NFS I/O, if known, and cached by Oracle ZFS Storage Appliance. There are some circumstances where the filename is not known, such as after a cluster failover. and when clients continue to operate on NFS file handles without issuing an open request to identify the filename; in these situations the filename reported is <unknown>.

Application ID

Identity of the client application issuing the I/O. This breakdown is available only for OISP-enabled NFSv4.0 and NFSv4.1 clients.

share

The share for this NFS I/O.

project

The project for this NFS I/O.

latency

A heat map showing the latency of NFS I/O, as measured from when the NFS request arrived on Oracle ZFS Storage Appliance from the network, to when the response is sent; this latency includes the time to process the NFS request, and to perform any disk I/O.

size

A heat map showing the distribution of NFS I/O sizes.

offset

A heat map showing the file offset of NFS I/O. This can be used to identify random or sequential NFS IOPS. Use the Disk I/O operations statistic to check whether random NFS 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: NFSv3 operations per second of type read broken down by latency (to examine latency for reads only)

  • Protocol: NFSv3 operations per second for file '/export/fs4/10ga' broken down by offset (to examine file access pattern for a particular file)

  • Protocol: NFSv3 operations per second for client hostname.example.com broken down by filename (to view which files a particular client is accessing)

Further Analysis