IBM Infosphere CDC for solidDB® system requirements
Disk space requirements
IBM Infosphere CDC source system:
▪100 GB—Default value for the Staging Store Disk Quota for each instance of IBM Infosphere CDC. Use the IBM Infosphere CDC configuration tool to configure disk space for this quota.
▪5 GB—For installation files, data queues, and log files.
▪Global disk quota—Disk space is required on your source system for this quota which is used to store in-scope change data that has not been committed in your database. The amount of disk space required is determined by your replication environment and the workload of your source database. Use the mirror_global_disk_quota_gb system parameter to configure the amount of disk space used by this quota.
IBM Infosphere CDC target system:
▪1 GB—The minimum amount of disk space allowed for the Staging Store Disk Quota for each instance of IBM Infosphere CDC. The minimum value for this quota is sufficient for all instances created on your target system. Use the IBM Infosphere CDC configuration tool to configure the disk space for this quota.
▪5 GB—For installation files, data queues, and log files.
▪Global disk quota—Disk space is required on your target system for this quota which is used to store LOB data received from your IBM Infosphere CDC source system. The amount of disk space required is determined by your replication environment and the amount of LOB data you are replicating. To improve performance, IBM Infosphere CDC will only persist LOB data to disk if RAM is not available on your target system. Use the mirror_global_disk_quota_gb system parameter to configure the amount of disk space used by this quota.
IBM Infosphere CDC may require additional disk space in the following situations:
▪You are running large batch transactions in the database on your source system.
▪You are configuring multiple subscriptions and one of your subscriptions is latent. In this type of scenario, IBM Infosphere CDC on your source system may persist transaction queues to disk if RAM is not available.
▪You are replicating large LOB data types.
▪You are replicating "wide" tables that have hundreds of columns.
▪You are performing regular back ups of your metadata with the dmbackupmd command-line utility.
RAM requirements
Each instance of IBM Infosphere CDC requires memory for the Java Virtual Machine (JVM). The following default values for memory are assigned:
▪1024 MB of RAM—Default value for each 64-bit instance of IBM Infosphere CDC.
▪512 MB of RAM—Default value for each 32-bit instance of IBM Infosphere CDC. Use the IBM Infosphere CDC configuration tool to configure the memory for each instance of IBM Infosphere CDC.
Note IBM Infosphere CDC is predominantly a Java-based application. However, some portions of it are written in C. These portions of IBM Infosphere CDC are not subject to the memory limits specified for the JVM.
Although IBM Infosphere CDC memory requirements will fluctuate, you must work with your system administrator to ensure the allocated memory for each instance of the product is available at all times. This may involve deployment planning since other applications with memory requirements may be installed on the same server with IBM Infosphere CDC. Using values other than the defaults or allocating more RAM than is physically available on your server should only be undertaken after considering the impacts on product performance.
IBM Infosphere CDC source deployments may require additional RAM in the following scenarios:
▪You are replicating large LOB data types with your IBM Infosphere CDC source deployment. These data types are sent to target while being retrieved from the source database. The target waits until all LOBs (for each record) are received before applying a row. LOBs are stored in memory as long as there is adequate RAM, otherwise they are written to disk on the target.
▪You are replicating "wide" tables with hundreds of columns.
▪You are performing large batch transactions in your source database rather than online transaction processing (OLTP).
Port requirements
IBM Infosphere CDC requires that you allocate a set of ports for communications with other components in the replication environment. The ports must be accessible through firewalls, although you do not require access to the internet.
Protocol
Default port
Purpose
TCP
11101
Accepts connections from:
▪Management Console
▪Other installations of IBM Infosphere CDC as a source of replication