- High Performance Backups
- Backup Consistency Level
- Split OFUSER Directory Backup for Speed.
These options impact the performance of backups; and, depending on the environment, they can have varied results from slowing down the backup to speeding it up.
Each customer should keep a log that tracks backup times correlated with Reload settings to determine the optimal settings for their environment.
High (High Performance Standard Backups)
This setting allows Reload to launch multiple backup processes simultaneously. Its behavior depends upon the Consistency setting:
Consistency = High/Highest: It will launch the backup of the user databases followed by the indexes. Once that it complete, it begins the backup process of the BLOBS (a.k.a., “offiles” or “attachments” directory) as well as the message databases. These run simultaneously.
“Highest” differs from “High” in that it verifies that every user database in the post office got copied down to the backup.
Consistency = Normal: It will launch the backup of the user databases and immediately launch the BLOBS backup as well. While the BLOBS are being backed up, the user databases typically finish beforehand and so the index backup begins. The BLOBS may still be backing up when the indexes are finished. Once the indexes are done, the message database backup begins.
In some environments, this setting speeds up the backup. If speed is the highest priority, then consider setting Consistency to “normal”.
When High Performance is disabled, each backup process runs serially one by one. The user databases are the first to be backed up, followed by the indexes, the message databases, and finally the BLOBS.
A slow WAN link or slow I/O may be factors that would cause an administrator to consider disabling this option. Another factor for considering disabling this option would be troubleshooting a backup. It is easier to read the logs if the processes are launched one after the other rather than simultaneously; in addition, having multiple processes running at once might be the issue under certain circumstances.
But again, experiment with your environment and be sure to log the results until you find the optimal setting.
Consistency (Backup Consistency Level)
As you can tell, this option affects the order of the processes within the backup. Consistency should be set to high in most circumstances, unless the POA is unloaded or there is a high level of confidence that the production message store will not change during the backup process (additions/deletions). It is the default setting except for Reload to Reload profiles, where the “post office” it is backing up is actually a Reload profile; yet, again, if there is a chance that the primary Reload profile you are backing up will change (i.e., Access Mode, Restore Mode, or DR), then set Consistency to high.
Split (Split OFUSER Directory Backup for Speed)
With this setting enabled, Reload divides the backup of the OFUSER and OFUSER / INDEX directories into two separate backup processes. This allows Reload to start backing up the OFFILES directory sooner, which results in a quicker backup; however, when a post office has several thousand users, this setting can actually slow down the backup performance. Consider disabling this setting if the post office has more than 3,000 users. But, again, we recommend that you test the performance with it enabled and disabled to see what is best in your environment.