Add up the following sizes to determine the minimum physical memory size required.
Shared memory size
JVM heap memory size
ActiveSpaces® Transactions runtime executable size
Operating system size
Non-ActiveSpaces® Transactions process sizes
Example:
A ActiveSpaces® Transactions application using highly available objects with a single active node and a single replica node on separate machines.
Size of application highly available object - 4 kilobytes Number of highly available objects persisted - 1000000 4096 * 1000000 = 4096000000 bytes (approximately 4 gigabytes). Number of transactional objects modified per transaction - 4 Amount of memory modified per object - 8192 bytes Number of concurrent transactions - 64 4 * 8192 * 64 = 2097152 bytes Primary Machine: 70 Megabytes (runtime shared memory footprint) 4096 Megabytes (highly available objects persisted in shared memory) 2 Megabytes (in flight transactions) 100 Megabytes (ActiveSpaces® Transactions process memory) =========================== 4268 Megabytes + JVM memory + Operating system memory + Other processes memory The backup machine has the same memory requirements as the primary machine.