diff --git a/src/cloudron.js b/src/cloudron.js
index 3220d64bf..2945a1a28 100644
--- a/src/cloudron.js
+++ b/src/cloudron.js
@@ -19,6 +19,8 @@ exports = module.exports = {
     renewCerts,
     syncDnsRecords,
 
+    updateDiskUsage,
+
     runSystemChecks
 };
 
@@ -344,3 +346,9 @@ async function syncDnsRecords(options) {
     tasks.startTask(taskId, {});
     return taskId;
 }
+
+async function updateDiskUsage() {
+    const taskId = await tasks.add(tasks.TASK_UPDATE_DISK_USAGE, []);
+    tasks.startTask(taskId, {});
+    return taskId;
+}
diff --git a/src/paths.js b/src/paths.js
index af72f9f34..29bfda241 100644
--- a/src/paths.js
+++ b/src/paths.js
@@ -38,6 +38,7 @@ exports = module.exports = {
     BACKUP_INFO_DIR: path.join(baseDir(), 'platformdata/backup'),
     UPDATE_DIR: path.join(baseDir(), 'platformdata/update'),
     UPDATE_CHECKER_FILE: path.join(baseDir(), 'platformdata/update/updatechecker.json'),
+    DISK_USAGE_FILE: path.join(baseDir(), 'platformdata/diskusage.json'),
     SNAPSHOT_INFO_FILE: path.join(baseDir(), 'platformdata/backup/snapshot-info.json'),
     DYNDNS_INFO_FILE: path.join(baseDir(), 'platformdata/dyndns-info.json'),
     DHPARAMS_FILE: path.join(baseDir(), 'platformdata/dhparams.pem'),
diff --git a/src/routes/cloudron.js b/src/routes/cloudron.js
index 8af6e1b78..a9c3a1a90 100644
--- a/src/routes/cloudron.js
+++ b/src/routes/cloudron.js
@@ -10,6 +10,8 @@ exports = module.exports = {
     isRebootRequired,
     getConfig,
     getDisks,
+    getDiskUsage,
+    updateDiskUsage,
     getMemory,
     getUpdateInfo,
     update,
@@ -169,6 +171,20 @@ async function getDisks(req, res, next) {
     next(new HttpSuccess(200, { disks: result }));
 }
 
+async function getDiskUsage(req, res, next) {
+    const [error, result] = await safe(system.getDiskUsage());
+    if (error) return next(BoxError.toHttpError(error));
+
+    next(new HttpSuccess(201, { usage: result }));
+}
+
+async function updateDiskUsage(req, res, next) {
+    const [error, taskId] = await safe(cloudron.updateDiskUsage());
+    if (error) return next(BoxError.toHttpError(error));
+
+    next(new HttpSuccess(201, { taskId }));
+}
+
 async function getMemory(req, res, next) {
     const [error, result] = await safe(system.getMemory());
     if (error) return next(BoxError.toHttpError(error));
diff --git a/src/server.js b/src/server.js
index 0c413a070..0e3fb7f2e 100644
--- a/src/server.js
+++ b/src/server.js
@@ -118,6 +118,8 @@ function initializeExpressSync() {
     router.post('/api/v1/cloudron/reboot',                   json, token, authorizeAdmin, routes.cloudron.reboot);
     router.get ('/api/v1/cloudron/graphs',                         token, authorizeAdmin, routes.graphs.getSystemGraphs);
     router.get ('/api/v1/cloudron/disks',                          token, authorizeAdmin, routes.cloudron.getDisks);
+    router.get ('/api/v1/cloudron/disk_usage',                     token, authorizeAdmin, routes.cloudron.getDiskUsage);
+    router.post('/api/v1/cloudron/disk_usage',                     token, authorizeAdmin, routes.cloudron.updateDiskUsage);
     router.get ('/api/v1/cloudron/memory',                         token, authorizeAdmin, routes.cloudron.getMemory);
     router.get ('/api/v1/cloudron/logs/:unit',                     token, authorizeAdmin, routes.cloudron.getLogs);
     router.get ('/api/v1/cloudron/logstream/:unit',                token, authorizeAdmin, routes.cloudron.getLogStream);
diff --git a/src/system.js b/src/system.js
index 13a153b38..956f75037 100644
--- a/src/system.js
+++ b/src/system.js
@@ -5,7 +5,8 @@ exports = module.exports = {
     checkDiskSpace,
     getMemory,
     getMemoryAllocation,
-    du
+    getDiskUsage,
+    updateDiskUsage
 };
 
 const apps = require('./apps.js'),
@@ -145,3 +146,39 @@ function getMemoryAllocation(limit) {
 
     return Math.round(Math.round(limit * ratio) / 1048576) * 1048576; // nearest MB
 }
+
+function getDiskUsage() {
+    const output = safe.JSON.parse(safe.fs.readFileSync(paths.DISK_USAGE_FILE, 'utf8'));
+    return output;
+}
+
+async function updateDiskUsage(progressCallback) {
+    assert.strictEqual(progressCallback, 'function');
+
+    const disks = await getDisks();
+    const filesystems = Object.keys(disks);
+    const now = Date.now();
+
+    let percent = 1;
+
+    for (const filesystem of filesystems) {
+        const disk = disks[filesystem];
+
+        percent += (100/filesystems.length);
+        progressCallback({ percent, message: `Checking contents of ${filesystem}`});
+
+        for (const content of disk.contents) {
+            progressCallback({ message: `Checking du of ${JSON.stringify(content)}`});
+            if (content.type === 'docker') {
+                content.usage = (await docker.du()).LayersSize;
+            } else {
+                content.usage = await du(content.path, { exclude: content.exclude });
+            }
+            progressCallback({ message: `du of ${JSON.stringify(content)}: ${content.usage}`});
+        }
+    }
+
+    if (!safe.fs.writeFileSync(paths.DISK_USAGE_FILE, JSON.stringify({ ts: now, disks }), 'utf8')) throw new BoxError(BoxError.FS_ERROR, `Could not write du cache file: ${safe.error.message}`);
+
+    return disks;
+}
diff --git a/src/tasks.js b/src/tasks.js
index a2d11cce2..c0ee9d6a2 100644
--- a/src/tasks.js
+++ b/src/tasks.js
@@ -28,6 +28,7 @@ exports = module.exports = {
     TASK_SYNC_EXTERNAL_LDAP: 'syncExternalLdap',
     TASK_CHANGE_MAIL_LOCATION: 'changeMailLocation',
     TASK_SYNC_DNS_RECORDS: 'syncDnsRecords',
+    TASK_UPDATE_DISK_USAGE: 'updateDiskUsage',
 
     // error codes
     ESTOPPED: 'stopped',
diff --git a/src/taskworker.js b/src/taskworker.js
index 3a5715809..46c9ccf50 100755
--- a/src/taskworker.js
+++ b/src/taskworker.js
@@ -15,6 +15,7 @@ const apptask = require('./apptask.js'),
     reverseProxy = require('./reverseproxy.js'),
     safe = require('safetydance'),
     settings = require('./settings.js'),
+    system = require('./system.js'),
     tasks = require('./tasks.js'),
     updater = require('./updater.js');
 
@@ -28,6 +29,7 @@ const TASKS = { // indexed by task type
     syncExternalLdap: externalLdap.sync,
     changeMailLocation: mail.changeLocation,
     syncDnsRecords: dns.syncDnsRecords,
+    updateDiskUsage: system.updateDiskUsage,
 
     _identity: async (arg, progressCallback) => { progressCallback(); return arg; },
     _error: async (arg, progressCallback) => { progressCallback(); throw new Error(`Failed for arg: ${arg}`); },