NAS Performance Tuning Tips and FAQs
If StorNext NAS is not running on your nodes after a StorNext platform upgrade completes, the NAS controller may be disabled. If the NAS controller has been disabled, delete the etc/init/snnas_controller.override file and restart the NAS controller.
- Log in to the console command line. See Access the Console Command Line.
- At the prompt, enter the following:
If the following error is returned, the NAS controller has been disabled:
Controller not running error: request to POST failed
- At the root shell prompt, enter the following command to verify that the NAS 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.
- Log in to the console command line as the StorNext admin user. See Access the Console Command Line.
- At the prompt, enter the following two lines to log in to the rootsh shell:
- At the rootsh shell prompt, enter the following to delete the etc/init/snnas_controller.override file.
# del /etc/init/snnas_controller.override
- At the prompt, enter the following to restart the NAS controller:
# initctl start snnas_controller
The default StorNext file system mount options are not optimized for StorNext NAS. If StorNext NAS performance is not optimal, you may need to tune StorNext to optimize performance.
We recommend tuning the following.
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: 256 KB
- Recommended setting for random I/O (such as database applications): typical read/write size
If your typical read/write size is 8 KB, set the cache buffer size to 8 KB.
- Default setting: 64 KB
- Keep in mind that when you set the cache buffer size value, the StorNext file system will read/write the entire buffer size. So even if you are modifying a file that is only 4 KB, if you set the cache buffer size to 256 KB, the system will read/write the entire 256 KB data block.
- When you increase the cache buffer size, you must also increase the buffer cache cap. See buffercachecap.
- You must optimize the raid array performance. See The Underlying Storage System in the StorNext 5 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): 4096 MB or 8192 MB
- Default Setting: 256 MB
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 StorNext NAS System. By increasing this value, the StorNext NAS 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
$ snfs1 /stornext/snfs1 cvfs
$ rw,cachebufsize=256k,buffercachecap=4096,dircachesize=32m,buffercache_iods=16 0 0
For additional information, see the StorNext 5 Tuning Guide and the StorNext 5 Man Pages Reference Guide.
Note: This issue applies to Mac OS X 10.11.5+ and Mac OS Sierra.
Apple's forced default of SMB client signing can cause significant decreases in SMB file transfer times on your Mac OS X 10.11.5+ or Mac OS Sierra. To resolve this issue, disable the forced client-signing on all necessary Mac clients.
- From the Mac client, access the /etc/nsmb.conf file.
- Populate this file with the following lines:
- Unmount and remount the SMB share.
SMB file transfer times should return to normal.