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Several FairCom DB configurations have been modified, which will result in increased storage for transaction logs. Please note the following changes and configurations as applied to your environment.
LOG_SPACE
Total transaction log space has been increased to 1GB total space in default ctsrvr.cfg configuration files - LOG_SPACE. This means each log now consumes 1/4, or 256MB of persisted storage space, including the log templates. As a result, your transaction log volume will now increase to 1GB on startup - three log templates and an active log. This will grow to 1.75GB when logs reach a steady state of default four log retention.
A change in logic allows us to avoid performing a long series of synchronous writes to the transaction log when we start the server in an empty transaction log directory.
This change significantly speeds up server startup on Linux when the file system has write barriers enabled.
Note: When write barriers are disabled on Linux, synchronous writes are much faster than with write barriers enabled, so FairCom highly recommends running with write barriers off and a battery backed power supply on the machine in production systems for best performance.
With this performance improvement, we have been able to increase LOG_SPACE to 1 GB and we have COMPATIBILITY LOG_WRITETHRU on by default.
The defaults in the Server Configuration File (ctsrvr.cfg) have been modified to optimize performance on modern systems.
LOG_SPACE 1 GB
PAGE_SIZE 32768
Warning: Changing the PAGE_SIZE is a maintenance task that should be done carefully and with a full reliable backup. Practice on a copy of your data and server folder until you are confident with the results. For procedures, see Adjusting PAGE_SIZE in the FairCom Installation Guide.
Note: A file created with a larger PAGE_SIZE cannot be opened by a server with a smaller PAGE_SIZE.
MAX_REPL_LOGS
MAX_REPL_LOGS default has been increased to 100. This applies when replication is active and logs begin to accumulate when replication is temporarily disconnected or falls behind. With the accompanying LOG_SPACE increase this can substantially increase persisted storage space requirements for transaction log volumes. That is, up to 100+ 256MB logs may be retained.
MAX_DFRIDX_LOGS
MAX_DFRIDX_LOGS default has been increased to 100. This applies when deferred indexing is active and logs begin to accumulate when indexing is temporarily disabled or falls behind. With the accompanying LOG_SPACE increase this can substantially increase persisted storage space requirements for transaction log volumes. That is, up to 100+ 256MB logs may be retained.
Tip - If you find error 96 on startup due to logs not found, it is likely be due to MAX_DFRIDX_LOGS or MAX_REPL_LOGS settings removing logs after the max is reached. Be sure to review your operational environment for appropriate settings.
