+ @Override
+ public void captureSnapshotIfReady(ReplicatedLogEntry replicatedLogEntry) {
+ long journalSize = replicatedLogEntry.getIndex() + 1;
+ long dataThreshold = context.getTotalMemory() *
+ context.getConfigParams().getSnapshotDataThresholdPercentage() / 100;
+
+ if ((journalSize % context.getConfigParams().getSnapshotBatchCount() == 0
+ || getDataSizeForSnapshotCheck() > dataThreshold)) {
+
+ boolean started = context.getSnapshotManager().capture(replicatedLogEntry,
+ currentBehavior.getReplicatedToAllIndex());
+ if (started) {
+ if (!context.hasFollowers()) {
+ dataSizeSinceLastSnapshot = 0;
+ }
+ }
+ }
+ }
+
+ private long getDataSizeForSnapshotCheck() {
+ long dataSizeForCheck = dataSize();
+ if (!context.hasFollowers()) {
+ // When we do not have followers we do not maintain an in-memory log
+ // due to this the journalSize will never become anything close to the
+ // snapshot batch count. In fact will mostly be 1.
+ // Similarly since the journal's dataSize depends on the entries in the
+ // journal the journal's dataSize will never reach a value close to the
+ // memory threshold.
+ // By maintaining the dataSize outside the journal we are tracking essentially
+ // what we have written to the disk however since we no longer are in
+ // need of doing a snapshot just for the sake of freeing up memory we adjust
+ // the real size of data by the DATA_SIZE_DIVIDER so that we do not snapshot as often
+ // as if we were maintaining a real snapshot
+ dataSizeForCheck = dataSizeSinceLastSnapshot / DATA_SIZE_DIVIDER;
+ }
+ return dataSizeForCheck;
+ }
+