Optimizing a System with Disk Stores

Optimize availability and performance by following the guidelines in this section.

1. VMware GemFire recommends the use of ext4 filesystems when operating on Linux or Solaris platforms. The ext4 filesystem supports preallocation, which benefits disk startup performance. If you are using ext3 filesystems in latency-sensitive environments with high write throughput, you can improve disk startup performance by setting the maxOplogSize (see the DiskStoreFactory.setMaxOplogSize) to a value lower than the default 1 GB and by disabling preallocation by specifying the system property gemfire.preAllocateDisk=false upon VMware GemFire process startup.
2. When you start your system, start all the members that have persistent regions at roughly the same time. Create and use startup scripts for consistency and completeness.
3. Shut down your system using the gfsh shutdown command. This is an ordered shutdown that positions your disk stores for a faster startup.
4. Configure critical usage thresholds (disk-usage-warning-percentage and disk-usage-critical-percentage) for the disk. By default, these are set to 80% for warning and 99% for errors that will shut down the cache.
5. Decide on a file compaction policy and, if needed, develop procedures to monitor your files and execute regular compaction.
6. Decide on a backup strategy for your disk stores and follow it. You can back up a running sytem by using the backup disk-store command.
7. If you remove any persistent region or change its configuration while your disk store is offline, consider synchronizing the regions in your disk stores.