Performance Tuning Tips and FAQs

1. Log in to the Appliance Controller CLI.
2. Enter:

   nascluster show

   If the following error is returned, the Appliance Controller has been disabled:

   Controller not running error: request to POST failed

3. At the root shell prompt, enter the following command to verify that the Appliance Controller has been disabled by the etc/init/snnas_controller.override file:

   # ls /etc/init/snnas_controller.override

   If the /etc/init/snnas_controller.override file is returned, delete it. See Resolution.

1. Log in to the command line using the following credentials:
   • User name: stornext
   • Password: <StorNext user account password>

     Note: password is the default password for the stornext user account. If the password has been changed, use the current password. The first time you log in, you are prompted to change the password to a different one.

2. Enter sudo rootsh to gain root user access.
3. Enter the password for the stornext user account again.
1. Enter the following to delete the etc/init/snnas_controller.override file:

   # del /etc/init/snnas_controller.override

2. At the prompt, enter the following to restart the Appliance Controller:

   # initctl start snnas_controller

The cache buffer size is the amount of data that will be processed as a single block from the StorNext file system.

• Recommended setting for sequential I/O: See the mount_cvfs and cvtune man pages.
• Recommended setting for random I/O (such as database applications): typical read/write size

  Example

  If your typical read/write size is small (less than 32 KB) and random, set the cache buffer size to 64 KB.

• Default setting: See the mount_cvfs and cvtune man pages.

  Important

  • Keep in mind that when you set the cache buffer size value, the StorNext file system will read/write the entire buffer size if the I/O is within EOF. If the workflow is writing I/O within a file that is only 4 KB and does not write the rest of the "cachebufsize", the system must read-modify-write the entire cachebufsize data block.
  • When you increase the cache buffer size, you should also consider the buffer cache cap. See buffercachecap.
  • You must optimize the raid array performance. See The Underlying Storage System in the StorNext 7 Documentation Center.

The buffer cache cap is the total amount of memory reserved for caching data. The reserved cache memory is shared by all mount points with the same cache size.

• Recommended Setting (dependent upon the amount of available memory): See the mount_cvfs and cvtune man pages.
• Default Setting: See the mount_cvfs and cvtune man pages.

When reserving cache memory, you need to take into account all processes that run on your system, such as smbd and FSM, so that you don't oversubscribe your system.

The directory cache size sets the size of the directory information cache on the Appliance Controller System. By increasing this value, the Appliance Controller System is able to keep more directory structure data in memory, dramatically improving the speed of readdir operations by reducing metadata network message traffic between it and FSM.

• Recommend Setting: 32 MB
• Default Setting: 10 MB

The buffer cache I/O daemons setting defines the number of background daemons used for performing buffer cache I/O.

• Recommended Setting: 16
• Default Setting: 8

For best performance, consider modifying the following client settings:

Record buffer size

In ProTools 11, the default record buffer is around 25 seconds. We recommend increasing the record buffer if multiple tracks are being written together.

RAM

Ensure that the client system has sufficient RAM to configure Disk Cache for playback:

OS Memory + Playback Cache + Extra GB of Insurance

For best performance, consider modifying the following StorNext settings:

ASR

With high stream counts, we recommend setting Allocation Session Reservation (ASR) to 256 MB to keep the streams from interleaving. The default setting of 1 GB is overkill for audio settings.

For more information about ASR, see Allocation Session Reservation (ASR) in the StorNext 7 Documentation Center.

Client Buffer Cache

We recommend increasing client buffer cache settings to 1GB or more to smooth record and play back.

Buffer Cache IODs

For high track count environments, we recommend that you add spindles to help with Buffer Cache IODs. The additional spindles help to address the potential limiting factor of disk actuators as the disks are seeking across multiple tracks.

1. From the Mac client, access the /etc/nsmb.conf file.
2. Populate this file with the following lines:

   [default]

   signing_required=no

3. Unmount and remount the SMB share.

   SMB file transfer times should return to normal.