Track the storage capacity and the total data/temp directory sizes

Nodes will stop proactively storing new data when they reach 90% capacity.

A new "maxStorageCapacity" setting has been added to allow the user to optionally limit the allocated space for this node. Limits are approximate only, not exact.

src/main/java/org/qortal/controller/Controller.java

@@ -54,6 +54,7 @@ import org.qortal.controller.arbitrary.ArbitraryDataBuildManager;
 import org.qortal.controller.arbitrary.ArbitraryDataCleanupManager;
 import org.qortal.controller.arbitrary.ArbitraryDataManager;
 import org.qortal.controller.Synchronizer.SynchronizationResult;
+import org.qortal.controller.arbitrary.ArbitraryDataStorageManager;
 import org.qortal.controller.repository.PruneManager;
 import org.qortal.controller.repository.NamesDatabaseIntegrityCheck;
 import org.qortal.controller.tradebot.TradeBot;
@@ -490,6 +491,7 @@ public class Controller extends Thread {
 		ArbitraryDataManager.getInstance().start();
 		ArbitraryDataBuildManager.getInstance().start();
 		ArbitraryDataCleanupManager.getInstance().start();
+		ArbitraryDataStorageManager.getInstance().start();
 
 		// Auto-update service?
 		if (Settings.getInstance().isAutoUpdateEnabled()) {
@@ -1080,6 +1082,7 @@ public class Controller extends Thread {
 				ArbitraryDataManager.getInstance().shutdown();
 				ArbitraryDataBuildManager.getInstance().shutdown();
 				ArbitraryDataCleanupManager.getInstance().shutdown();
+				ArbitraryDataStorageManager.getInstance().shutdown();
 
 				if (blockMinter != null) {
 					LOGGER.info("Shutting down block minter");

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataCleanupManager.java

@@ -76,6 +76,11 @@ public class ArbitraryDataCleanupManager extends Thread {
 					continue;
 				}
 
+				// Wait until storage capacity has been calculated
+				if (!storageManager.isStorageCapacityCalculated()) {
+					continue;
+				}
+
 				// Periodically delete any unnecessary files from the temp directory
 				if (offset == 0 || offset % (limit * 10) == 0) {
 					this.cleanupTempDirectory(now);

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataStorageManager.java

@@ -1,10 +1,20 @@
 package org.qortal.controller.arbitrary;
 
+import org.apache.commons.io.FileUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.list.ResourceListManager;
 import org.qortal.settings.Settings;
+import org.qortal.utils.FilesystemUtils;
+import org.qortal.utils.NTP;
 
-public class ArbitraryDataStorageManager {
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+public class ArbitraryDataStorageManager extends Thread {
 
     public enum StoragePolicy {
         FOLLOWED_AND_VIEWED,
@@ -14,7 +24,21 @@ public class ArbitraryDataStorageManager {
         NONE
     }
 
+    private static final Logger LOGGER = LogManager.getLogger(ArbitraryDataStorageManager.class);
+
     private static ArbitraryDataStorageManager instance;
+    private volatile boolean isStopping = false;
+
+    private Long storageCapacity = null;
+    private long totalDirectorySize = 0L;
+    private long lastDirectorySizeCheck = 0;
+
+    private static long DIRECTORY_SIZE_CHECK_INTERVAL = 10 * 60 * 1000L; // 10 minutes
+
+    /** Treat storage as full at 90% usage, to reduce risk of going over the limit.
+     * This is necessary because we don't calculate total storage values before every write.
+     * It also helps avoid a fetch/delete loop, as we will stop fetching before the hard limit. */
+    private static double STORAGE_FULL_THRESHOLD = 0.9; // 90%
 
     public ArbitraryDataStorageManager() {
     }
@@ -26,6 +50,42 @@ public class ArbitraryDataStorageManager {
         return instance;
     }
 
+    @Override
+    public void run() {
+        Thread.currentThread().setName("Arbitrary Data Storage Manager");
+        try {
+            while (!isStopping) {
+                Thread.sleep(1000);
+
+                Long now = NTP.getTime();
+                if (now == null) {
+                    continue;
+                }
+
+                // Check the total directory size if we haven't in a while
+                if (this.shouldCalculateDirectorySize(now)) {
+                    this.calculateDirectorySize(now);
+                }
+
+                Thread.sleep(59000);
+            }
+        } catch (InterruptedException e) {
+            // Fall-through to exit thread...
+        }
+    }
+
+    public void shutdown() {
+        isStopping = true;
+        this.interrupt();
+    }
+
+    /**
+     * Check if data relating to a transaction is allowed to
+     * exist on this node, therefore making it a mirror for this data.
+     *
+     * @param arbitraryTransactionData - the transaction
+     * @return boolean - whether to prefetch or not
+     */
     public boolean canStoreData(ArbitraryTransactionData arbitraryTransactionData) {
         String name = arbitraryTransactionData.getName();
 
@@ -34,6 +94,8 @@ public class ArbitraryDataStorageManager {
             return false;
         }
 
+        // Don't check for storage limits here, as it can cause the cleanup manager to delete existing data
+
         // Check if our storage policy and blacklist allows us to host data for this name
         switch (Settings.getInstance().getStoragePolicy()) {
             case FOLLOWED_AND_VIEWED:
@@ -53,20 +115,38 @@ public class ArbitraryDataStorageManager {
         }
     }
 
+    /**
+     * Check if data relating to a transaction should be downloaded
+     * automatically, making this node a mirror for that data.
+     *
+     * @param arbitraryTransactionData - the transaction
+     * @return boolean - whether to prefetch or not
+     */
     public boolean shouldPreFetchData(ArbitraryTransactionData arbitraryTransactionData) {
         String name = arbitraryTransactionData.getName();
-        if (name == null) {
-            return this.shouldPreFetchDataWithoutName(arbitraryTransactionData);
-        }
-        // Never fetch data from blacklisted names, even if they are followed
-        if (this.isNameInBlacklist(name)) {
+
+        // Don't fetch anything more if we're (nearly) out of space
+        // Make sure to keep STORAGE_FULL_THRESHOLD considerably less than 1, to
+        // avoid a fetch/delete loop
+        if (!this.isStorageSpaceAvailable(STORAGE_FULL_THRESHOLD)) {
             return false;
         }
+
         // Don't store data unless it's an allowed type (public/private)
         if (!this.isDataTypeAllowed(arbitraryTransactionData)) {
             return false;
         }
 
+        // Handle transactions without names differently
+        if (name == null) {
+            return this.shouldPreFetchDataWithoutName();
+        }
+
+        // Never fetch data from blacklisted names, even if they are followed
+        if (this.isNameInBlacklist(name)) {
+            return false;
+        }
+
         switch (Settings.getInstance().getStoragePolicy()) {
             case FOLLOWED:
             case FOLLOWED_AND_VIEWED:
@@ -82,10 +162,17 @@ public class ArbitraryDataStorageManager {
         }
     }
 
-    private boolean shouldPreFetchDataWithoutName(ArbitraryTransactionData arbitraryTransactionData) {
+    /**
+     * Don't call this method directly.
+     * Use the wrapper method shouldPreFetchData() instead, as it contains
+     * additional checks.
+     *
+     * @return boolean - whether the storage policy allows for unnamed data
+     */
+    private boolean shouldPreFetchDataWithoutName() {
         switch (Settings.getInstance().getStoragePolicy()) {
             case ALL:
-                return this.isDataTypeAllowed(arbitraryTransactionData);
+                return true;
 
             case NONE:
             case VIEWED:
@@ -118,4 +205,105 @@ public class ArbitraryDataStorageManager {
     private boolean isFollowingName(String name) {
         return ResourceListManager.getInstance().listContains("followed", "names", name, false);
     }
+
+
+    // Size limits
+
+    /**
+     * Rate limit to reduce IO load
+     */
+    private boolean shouldCalculateDirectorySize(Long now) {
+        if (now == null) {
+            return false;
+        }
+        // If storage capacity is null, we need to calculate it
+        if (this.storageCapacity == null) {
+            return true;
+        }
+        // If we haven't checked for a while, we need to check it now
+        if (now - lastDirectorySizeCheck > DIRECTORY_SIZE_CHECK_INTERVAL) {
+            return true;
+        }
+
+        // We shouldn't check this time, as we want to reduce IO load on the SSD/HDD
+        return false;
+    }
+
+    private void calculateDirectorySize(Long now) {
+        if (now == null) {
+            return;
+        }
+
+        long totalSize = 0;
+        long remainingCapacity = 0;
+
+        // Calculate remaining capacity
+        try {
+            remainingCapacity = this.getRemainingUsableStorageCapacity();
+        } catch (IOException e) {
+            LOGGER.info("Unable to calculate remaining storage capacity: {}", e.getMessage());
+            return;
+        }
+
+        // Calculate total size of data directory
+        LOGGER.trace("Calculating data directory size...");
+        Path dataDirectoryPath = Paths.get(Settings.getInstance().getDataPath());
+        if (dataDirectoryPath.toFile().exists()) {
+            totalSize += FileUtils.sizeOfDirectory(dataDirectoryPath.toFile());
+        }
+
+        // Add total size of temp directory, if it's not already inside the data directory
+        Path tempDirectoryPath = Paths.get(Settings.getInstance().getTempDataPath());
+        if (tempDirectoryPath.toFile().exists()) {
+            if (!FilesystemUtils.isChild(tempDirectoryPath, dataDirectoryPath)) {
+                LOGGER.trace("Calculating temp directory size...");
+                totalSize += FileUtils.sizeOfDirectory(dataDirectoryPath.toFile());
+            }
+        }
+
+        this.totalDirectorySize = totalSize;
+        this.lastDirectorySizeCheck = now;
+
+        // It's essential that used space (this.totalDirectorySize) is included in the storage capacity
+        LOGGER.trace("Calculating total storage capacity...");
+        long storageCapacity = remainingCapacity + this.totalDirectorySize;
+
+        // Make sure to limit the storage capacity if the user is overriding it in the settings
+        if (Settings.getInstance().getMaxStorageCapacity() != null) {
+            storageCapacity = Math.min(storageCapacity, Settings.getInstance().getMaxStorageCapacity());
+        }
+        this.storageCapacity = storageCapacity;
+
+        LOGGER.info("Total used: {} bytes, Total capacity: {} bytes", this.totalDirectorySize, this.storageCapacity);
+    }
+
+    private long getRemainingUsableStorageCapacity() throws IOException {
+        // Create data directory if it doesn't exist so that we can perform calculations on it
+        Path dataDirectoryPath = Paths.get(Settings.getInstance().getDataPath());
+        if (!dataDirectoryPath.toFile().exists()) {
+            Files.createDirectories(dataDirectoryPath);
+        }
+
+        return dataDirectoryPath.toFile().getUsableSpace();
+    }
+
+    public long getTotalDirectorySize() {
+        return this.totalDirectorySize;
+    }
+
+    public boolean isStorageSpaceAvailable(double threshold) {
+        if (!this.isStorageCapacityCalculated()) {
+            return false;
+        }
+
+        long maxStorageCapacity = (long)((double)this.storageCapacity / 100.0f * threshold);
+        if (this.totalDirectorySize >= maxStorageCapacity) {
+            return false;
+        }
+        return true;
+    }
+
+    public boolean isStorageCapacityCalculated() {
+        return (this.storageCapacity != null);
+    }
 }

src/main/java/org/qortal/settings/Settings.java

@@ -289,6 +289,8 @@ public class Settings {
 	/** Whether to allow private (non-decryptable) data to be stored */
 	private boolean privateDataEnabled = false;
 
+	/** Maximum total size of hosted data, in bytes. Unlimited if null */
+	private Long maxStorageCapacity = null;
 
 	// Domain mapping
 	public static class DomainMap {
@@ -840,4 +842,8 @@ public class Settings {
 	public boolean isPrivateDataEnabled() {
 		return this.privateDataEnabled;
 	}
+
+	public Long getMaxStorageCapacity() {
+		return this.maxStorageCapacity;
+	}
 }

src/main/java/org/qortal/utils/FilesystemUtils.java

@@ -181,6 +181,10 @@ public class FilesystemUtils {
         return false;
     }
 
+    public static boolean isChild(Path child, Path parent) {
+        return child.toAbsolutePath().startsWith(parent.toAbsolutePath());
+    }
+
     public static long getDirectorySize(Path path) throws IOException {
         if (path == null || !Files.exists(path)) {
             return 0L;