3.5 Configuring the Target Service Agent for File System

TSAFS provides configurable parameters to help tune its performance. It also provides configurable parameters to control certain specific features that are supported by it.

3.5.1 Using iManager

Complete the following steps to configure the parameters used by TSA:

  1. In iManager, click SMS Backup and Restore, then click TSAFS Options.

    TSA configuration screen

  2. Select the server for which you need to modify the TSA configuration settings, using the eDirectory object selector.

  3. Enter the following values and click OK.

    • TSA Mode: TSA Mode can be used to expose NSS as a native Linux file system (Linux Mode) or emulate NetWare file system semantics (NetWare Mode) on OES Linux.

      If the Dual Mode is selected, both NetWare and Linux semantics are simultaneously exposed and can be used independent of each other. By default, the TSA Mode is set to Linux. This option is supported only on OES Linux.

      The changed value takes effect when you reload the tsafs module.

    • Read Buffer Size: The number of data bytes read from the file system by a single read operation.

      This parameter is based on the buffer size requested by the engine. For example, if the engine requests 64 KB of data for each read operation, set the buffer size to 64 KB to allow the TSAFS to service the engine better. By default this is set to 65536 bytes.

      For OES Linux, the modified value takes effect when you reload the tsafs module.

      For OES NetWare, the modified value takes effect from the next new connection onwards.

    • Read Threads Per Job: The number of read-ahead threads for a job. This enables the TSAFS to read data ahead of the engine request during backup. This switch is based on the number of processors in the system. The default value is 4 for a single or dual processor system. Set the read threads to a higher value if the system has more processors.

      For OES Linux, the changed value takes effect when you reload the tsafs module.

      For OES NetWare, the modified value takes effect from the next new connection onwards.

    • Read Thread Allocation: The percentage of Read Threads Per Job that processes a data set.

      Read Thread Allocation can be used to control the maximum number of read threads that may be allocated to process a single data set. By default, the Read Thread Allocation is set to 100 (%). It can have a value in the range 10 (%) to 100 (%). It is recommended that this value be set to 100 (%) if the backup application requests data sets serially.

    • Read Ahead Throttle: The maximum number of data sets that the TSA processes simultaneously.

      Read Ahead Throttle can be used to limit the number of simultaneous data sets that are being cached. In certain runtime scenarios, it helps in overriding the Read Thread Allocation in order to complete processing of large data sets. By default, the Read Ahead Throttle is set to 2. It can have a value in the range 1 to 32.

    • Cache Memory Threshold: The percentage of unallocated server memory that the TSA can utilize to store cached datasets. This represents a maximum percentage value of unallocated server memory that the TSA uses to store cached datasets. The default value is 25% of unallocated server memory. The cache memory utilized by the TSA is dynamically reset based on the available unallocated memory.

      For OES Linux, the modified value takes effect when you reload the tsafs module.

      For OES NetWare, the modified value takes effect when the TSAFS.NLM is reloaded.

    • Enable Caching: This option can be used to specify if the TSA should do predictive caching during backups. Caching improves backup performance, on certain workloads, by prefetching files in memory. By default, Enable Caching is selected.

      For OES Linux, the modified value takes effect when you reload the tsafs module.

      For OES NetWare, the modified value takes effect from the next new connection onwards

    • Enable Clustering: Determines cluster support. If the backup server does not support clusters, this option is disabled. Select this option if the TSA is running on a cluster node and the backup engine is cluster-enabled. Deselect it if the TSA is running on a non-cluster node or the backup engine is not cluster-enabled. This is selected by default.

      Running a cluster-enabled TSA on a non-cluster node does not affect functionality in any way.

      For OES Linux, the modified value takes effect when you reload the tsafs module.

      For OES NetWare, the modified value takes effect when the TSAFS.NLM is reloaded.

3.5.2 Using Server Console for OES NetWare

The following table provides information about the basic parameters and their usage:

Table 3-1 Basic Parameters

Task

Purpose

Command

Set the number of read threads for a job

This value enables the TSA to read data ahead of the engine request during backup. This switch is based on the number of processors in the system.

The default value is 4. Set the read threads to a higher value if you have more processors.

TSAFS / readthreadsperjob=value

Set the read buffer size

This value is the amount of data (bytes) read from the file system by a single read operation. This switch is based on the buffer sizes used by the engine. For example, if the engine requests 32 KB of data for each read operation, set the buffer size to 32 KB to allow the TSA to service the engine better.

This value is set in multiples of 512 bytes (sector size or the actual block size).

Another aspect to consider while setting the buffer is the mean size of the dataset being backed up. For example, if the mean size of the dataset is 28 KB, set the buffer size to 64 KB so additional memory is added to the mean size of the dataset. This is required for backup of file characteristics and SIDF encoding. The default value is 64 KB.

TSAFS /readbuffersize=value

Set the percentage of total server memory to store cached datasets.

This value is used to specify the percentage of total server memory that the TSA can utilize to store cached datasets. This represents a maximum percentage value of total server memory that the TSA uses to store cached datasets.

The default value is 25% of the total server memory.

TSAFS /CacheMemoryThreshold

Set the TSA to support failover or failback on cluster volumes.

Set this value to cluster if the TSA is running on a cluster node and the backup engine supports clusters.

Set this value to nocluster if the TSA is running on a cluster node or if the backup engine does not support clusters.

The default value is cluster.

Running a cluster-enabled TSA on a non-cluster-enabled node does not affect functionality in any way.

TSAFS /cluster|nocluster

Enable Caching in TSAFS

Set the value to cachingMode if the TSA should do predictive caching during backups. Caching improves backup performance, on certain workloads, by prefetching files in memory.

Set the value to noCachingMode if the TSA should not do predictive caching during backups.

The default value is cachingMode.

TSAFS /CachingMode | noCachingMode

For advanced configuration, refer to Section 5.3, Fine-Tuning SMS Performance.

To enable additional backup features, refer to Section 4.1.4, Additional Backup Features.

3.5.3 Using the Command Line for OES Linux

The Storage Management Data Requestor (SMDR) is a daemon process on Linux that holds the information regarding Target Service Agents (TSA) that have registered to it.

The process of registering or de-registering a TSA with SMDR is referred to as a loading or unloading the TSA. The TSAs should be registered with SMDR for the backup engines to access the specific target.

On OES Linux, /opt/novell/sms/bin/smsconfig is provided to load or unload the (TSA) with the SMDR daemon:

smsconfig [ -l | -u | -t] [TSA module name] [TSA options] ...

For example:

smsconfig -l tsafs

Registers the TSA, tsafs with SMDR

smsconfig -u tsafs

De-registers the TSA, tsafs from SMDR

smsconfig -t

List the TSAs currently registered with SMDR

smsconfig -l tsafs --tsaMode=Linux

Set the tsamode to linux to expose NSS as a native Linux file system.

Set the tsamode to netware to expose NSS with NetWare file system semantics.

Set the tsamode to dual, if both NetWare and Linux semantics should be simultaneously exposed and be used independent of each other.

The default value is linux.

The TSAs also expose their command line configuration interface to the user through smsconfig, which enables the user to configure the TSAs. For example, the following command can be used to see TSAFS configurable parameters:

smsconfig -l tsafs --help

TSAFS can be configured during registration as shown in the following example:

smsconfig -l tsafs --ReadThreadsPerJob=6

This configuration persists till the TSA is unloaded.

For more information regarding smsconfig and tsafs configurable parameters, refer to the smsconfig(1) man page or in the SMS man Pages section, view the HTML version and tsafs(1) man page or view its HTML version

For advanced configuration, refer to Section 5.3, Fine-Tuning SMS Performance.

To enable additional backup features, refer to Section 4.1.4, Additional Backup Features.

3.5.4 Using a Configuration File for OES Linux

The TSAFS configuration file is located at /etc/opt/novell/sms/tsafs.conf on OES Linux. When the TSA is loaded, it reads the configuration file for its default configuration.

For more information refer to the tsafs.conf(5) man page or in the SMS man Pages section, view the HTML version of the man page.