Ways to improve storage system performance
You can take configuration procedures to improve your system's performance.
- About balancing NFS traffic on network interfaces
You can attach multiple interfaces on the storage system to the same physical network to balance network traffic among different interfaces.
- How to ensure reliable NFS traffic by using TCP
With faster NICs and switches, you are advised to support NFSv2 or NFS v3 protocol over TCP rather than over UDP. NFS v4 is supported over TCP only.
- Avoiding access time update for inodes
If your applications do not depend on having the correct access time for files, you can disable the update of access time (atime) on an inode when a file is read.
- Improving read-ahead performance
If the file access patterns of your clients are random (nonsequential) and the cache age is less than three, setting minimal read-ahead to on might improve performance.
- Adding disks to a disk-bound aggregate
If you have a single traditional volume or single-aggregate storage system, you can determine the fraction of time that the busiest disk is active and add disks to the traditional volume or aggregate if necessary.
- About sizing aggregates appropriately
When creating an aggregate or a traditional volume, be sure to provide enough data disks for its anticipated data access load. Performance problems due to insufficient data disks are especially noticeable for single-data-disk aggregates (two disks for RAID4 and three disks for RAID-DP).
- About putting cards into the correct slots
At boot time or when you use the sysconfig -c command, you might see messages indicating that expansion cards must be in certain slots. To improve performance, follow the recommendations in the message.
- Maintaining adequate free blocks and free inodes
If free blocks or free inodes make up less than 10 percent of the space on any volume, the performance of writes and creates can suffer. You should check to ensure that you system has adequate free blocks and free inodes.
- About optimizing LUN, file, and volume layout
If read performance on a particular large file or LUN degrades over time, consider using the reallocate command to optimize its layout. If you add disks to an aggregate, use reallocate to redistribute the data equally across all of the disks in the aggregate.
- Using oplocks for CIFS storage systems
Oplocks (opportunistic locks) allow CIFS clients to cache more data locally, reducing traffic to the storage system.
- Increasing the TCP window size for CIFS
Increasing the TCP receive window size to its maximum setting on both the system and a CIFS client can improve performance for large transfers, provided that packet loss is not taking place and the client's send window is large.
- About backing up by using qtrees
If your storage system has multiple tape drives and a volume with two to four qtrees, you can improve backup rates by running multiple dump commands in parallel, each reading a different qtree and writing to a different tape drive.
