/**
* Determine whether a checkpoint should be run. 1. If the force parameter is specified, always
* checkpoint. 2. If the config object specifies time or log size, use that. 3. If the environment
* is configured to use log size based checkpointing, check the log. 4. Lastly, use time based
* checking.
*/
private boolean isRunnable(CheckpointConfig config) throws DatabaseException {
/* Figure out if we're using log size or time to determine interval.*/
long useBytesInterval = 0;
long useTimeInterval = 0;
DbLsn nextLsn = null;
try {
if (config.getForce()) {
return true;
} else if (config.getKBytes() != 0) {
useBytesInterval = config.getKBytes() << 10;
} else if (config.getMinutes() != 0) {
// convert to millis
useTimeInterval = config.getMinutes() * 60 * 1000;
} else if (logSizeBytesInterval != 0) {
useBytesInterval = logSizeBytesInterval;
} else {
useTimeInterval = timeInterval;
}
/*
* If our checkpoint interval is defined by log size, check
* on how much log has grown since the last checkpoint.
*/
if (useBytesInterval != 0) {
nextLsn = envImpl.getFileManager().getNextLsn();
if (nextLsn.getNoCleaningDistance(lastCheckpointEnd, logFileMax) >= useBytesInterval) {
return true;
} else {
return false;
}
} else if (useTimeInterval != 0) {
/*
* Our checkpoint is determined by time. If enough
* time has passed and some log data has been written,
* do a checkpoint.
*/
DbLsn lastUsedLsn = envImpl.getFileManager().getLastUsedLsn();
if (((System.currentTimeMillis() - lastCheckpointMillis) >= useTimeInterval)
&& (lastUsedLsn.compareTo(lastCheckpointEnd) != 0)) {
return true;
} else {
return false;
}
} else {
return false;
}
} finally {
StringBuffer sb = new StringBuffer();
sb.append("size interval=").append(useBytesInterval);
if (nextLsn != null) {
sb.append(" nextLsn=").append(nextLsn.getNoFormatString());
}
if (lastCheckpointEnd != null) {
sb.append(" lastCkpt=");
sb.append(lastCheckpointEnd.getNoFormatString());
}
sb.append(" time interval=").append(useTimeInterval);
sb.append(" force=").append(config.getForce());
Tracer.trace(Level.FINEST, envImpl, sb.toString());
}
}
