diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 0ccadaf5a95..4111c42c4d1 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -111,10 +111,8 @@ function parseArgs() {
     if (['true', 'false'].includes(v)) return v === 'true'
     throw new Error(`expected "true" or "false" for boolean option ${name}`)
   }
-  const BATCH_RANGE_START = objectIdFromInput(
-    args['BATCH_RANGE_START']
-  ).toString()
-  const BATCH_RANGE_END = objectIdFromInput(args['BATCH_RANGE_END']).toString()
+  const BATCH_RANGE_START = objectIdFromInput(args.BATCH_RANGE_START).toString()
+  const BATCH_RANGE_END = objectIdFromInput(args.BATCH_RANGE_END).toString()
   return {
     PROCESS_NON_DELETED_PROJECTS: boolVal('processNonDeletedProjects'),
     PROCESS_DELETED_PROJECTS: boolVal('processDeletedProjects'),
@@ -122,8 +120,8 @@ function parseArgs() {
     PROCESS_HASHED_FILES: boolVal('processHashedFiles'),
     BATCH_RANGE_START,
     BATCH_RANGE_END,
-    LOGGING_IDENTIFIER: args['LOGGING_IDENTIFIER'] || BATCH_RANGE_START,
-    PROJECT_IDS_FROM: args['projectIdsFrom'],
+    LOGGING_IDENTIFIER: args.LOGGING_IDENTIFIER || BATCH_RANGE_START,
+    PROJECT_IDS_FROM: args.projectIdsFrom,
   }
 }

@@ -249,8 +247,8 @@ let lastEventLoopStats = performance.eventLoopUtilization()
  * @param {number} ms
  */
 function toMiBPerSecond(v, ms) {
-  const ONE_MiB = 1024 * 1024
-  return v / ONE_MiB / (ms / 1000)
+  const MiB = 1024 * 1024
+  return v / MiB / (ms / 1000)
 }

 /**



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 4111c42c4d1..2d55b41b43e 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -84,11 +84,11 @@ ObjectId.cacheHexString = true
 function parseArgs() {
   const PUBLIC_LAUNCH_DATE = new Date('2012-01-01T00:00:00Z')
   const args = commandLineArgs([
-    { name: 'processNonDeletedProjects', type: String, defaultValue: 'false' },
-    { name: 'processDeletedProjects', type: String, defaultValue: 'false' },
-    { name: 'processHashedFiles', type: String, defaultValue: 'false' },
-    { name: 'processBlobs', type: String, defaultValue: 'true' },
-    { name: 'projectIdsFrom', type: String, defaultValue: '' },
+    { name: 'projects', type: Boolean },
+    { name: 'deleted-projects', type: Boolean },
+    { name: 'include-hashed-files', type: Boolean },
+    { name: 'skip-existing-blobs', type: Boolean },
+    { name: 'from-file', type: String, defaultValue: '' },
     {
       name: 'BATCH_RANGE_START',
       type: String,
@@ -99,29 +99,20 @@ function parseArgs() {
       type: String,
       defaultValue: new Date().toISOString(),
     },
-    { name: 'LOGGING_IDENTIFIER', type: String, defaultValue: '' },
+    { name: 'logging-id', type: String, defaultValue: '' },
   ])
-  /**
-   * commandLineArgs cannot handle --foo=false, so go the long way
-   * @param {string} name
-   * @return {boolean}
-   */
-  function boolVal(name) {
-    const v = args[name]
-    if (['true', 'false'].includes(v)) return v === 'true'
-    throw new Error(`expected "true" or "false" for boolean option ${name}`)
-  }
+
   const BATCH_RANGE_START = objectIdFromInput(args.BATCH_RANGE_START).toString()
   const BATCH_RANGE_END = objectIdFromInput(args.BATCH_RANGE_END).toString()
   return {
-    PROCESS_NON_DELETED_PROJECTS: boolVal('processNonDeletedProjects'),
-    PROCESS_DELETED_PROJECTS: boolVal('processDeletedProjects'),
-    PROCESS_BLOBS: boolVal('processBlobs'),
-    PROCESS_HASHED_FILES: boolVal('processHashedFiles'),
+    PROCESS_NON_DELETED_PROJECTS: args.projects,
+    PROCESS_DELETED_PROJECTS: args['deleted-projects'],
+    PROCESS_HASHED_FILES: args['include-hashed-files'],
+    PROCESS_BLOBS: !args['skip-existing-blobs'],
     BATCH_RANGE_START,
     BATCH_RANGE_END,
-    LOGGING_IDENTIFIER: args.LOGGING_IDENTIFIER || BATCH_RANGE_START,
-    PROJECT_IDS_FROM: args.projectIdsFrom,
+    LOGGING_IDENTIFIER: args['logging-id'] || BATCH_RANGE_START,
+    PROJECT_IDS_FROM: args['from-file'],
   }
 }

diff --git a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
index 62b0b1de25f..0f8bdbf3e1a 100644
--- a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
+++ b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
@@ -544,8 +544,8 @@ describe('back_fill_file_hash script', function () {
         process.argv0,
         [
           'storage/scripts/back_fill_file_hash.mjs',
-          '--processNonDeletedProjects=true',
-          '--processDeletedProjects=true',
+          '--projects',
+          '--deleted-projects',
           ...args,
         ],
         {
@@ -854,7 +854,7 @@ describe('back_fill_file_hash script', function () {
     // Practically, this is slow and moving it to the end of the tests gets us there most of the way.
     it('should process nothing on re-run', async function () {
       const rerun = await runScript(
-        processHashedFiles ? ['--processHashedFiles=true'] : [],
+        processHashedFiles ? ['--include-hashed-files'] : [],
         {},
         false
       )
@@ -1113,7 +1113,7 @@ describe('back_fill_file_hash script', function () {
       output1 = await runScript([], {})
     })
     before('run script with hashed files', async function () {
-      output2 = await runScript(['--processHashedFiles=true'], {})
+      output2 = await runScript(['--include-hashed-files'], {})
     })
     it('should print stats for the first run without hashed files', function () {
       expect(output1.stats).deep.equal(STATS_ALL)
@@ -1161,7 +1161,7 @@ describe('back_fill_file_hash script', function () {
     let output
     before('prepare environment', prepareEnvironment)
     before('run script', async function () {
-      output = await runScript(['--processHashedFiles=true'], {})
+      output = await runScript(['--include-hashed-files'], {})
     })
     it('should print stats', function () {
       expect(output.stats).deep.equal(
@@ -1263,10 +1263,10 @@ describe('back_fill_file_hash script', function () {

     let outputPart0, outputPart1
     before('run script on part 0', async function () {
-      outputPart0 = await runScript([`--projectIdsFrom=${path0}`])
+      outputPart0 = await runScript([`--from-file=${path0}`])
     })
     before('run script on part 1', async function () {
-      outputPart1 = await runScript([`--projectIdsFrom=${path1}`])
+      outputPart1 = await runScript([`--from-file=${path1}`])
     })

     /**



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 2d55b41b43e..68ce4b67aa2 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -79,7 +79,7 @@ ObjectId.cacheHexString = true
  */

 /**
- * @return {{PROJECT_IDS_FROM: string, PROCESS_HASHED_FILES: boolean, LOGGING_IDENTIFIER: string, BATCH_RANGE_START: string, PROCESS_BLOBS: boolean, BATCH_RANGE_END: string, PROCESS_NON_DELETED_PROJECTS: boolean, PROCESS_DELETED_PROJECTS: boolean}}
+ * @return {{PROJECT_IDS_FROM: string, PROCESS_HASHED_FILES: boolean, LOGGING_IDENTIFIER: string, BATCH_RANGE_START: string, PROCESS_BLOBS: boolean, BATCH_RANGE_END: string, PROCESS_NON_DELETED_PROJECTS: boolean, PROCESS_DELETED_PROJECTS: boolean, DRY_RUN: boolean}}
  */
 function parseArgs() {
   const PUBLIC_LAUNCH_DATE = new Date('2012-01-01T00:00:00Z')
@@ -89,6 +89,7 @@ function parseArgs() {
     { name: 'include-hashed-files', type: Boolean },
     { name: 'skip-existing-blobs', type: Boolean },
     { name: 'from-file', type: String, defaultValue: '' },
+    { name: 'dry-run', type: Boolean },
     {
       name: 'BATCH_RANGE_START',
       type: String,
@@ -109,6 +110,7 @@ function parseArgs() {
     PROCESS_DELETED_PROJECTS: args['deleted-projects'],
     PROCESS_HASHED_FILES: args['include-hashed-files'],
     PROCESS_BLOBS: !args['skip-existing-blobs'],
+    DRY_RUN: args['dry-run'],
     BATCH_RANGE_START,
     BATCH_RANGE_END,
     LOGGING_IDENTIFIER: args['logging-id'] || BATCH_RANGE_START,
@@ -121,6 +123,7 @@ const {
   PROCESS_DELETED_PROJECTS,
   PROCESS_BLOBS,
   PROCESS_HASHED_FILES,
+  DRY_RUN,
   BATCH_RANGE_START,
   BATCH_RANGE_END,
   LOGGING_IDENTIFIER,
@@ -325,10 +328,12 @@ async function processFileWithCleanup(entry) {
   try {
     return await processFile(entry, filePath)
   } finally {
-    await Promise.all([
-      fs.promises.rm(filePath, { force: true }),
-      fs.promises.rm(filePath + GZ_SUFFIX, { force: true }),
-    ])
+    if (!DRY_RUN) {
+      await Promise.all([
+        fs.promises.rm(filePath, { force: true }),
+        fs.promises.rm(filePath + GZ_SUFFIX, { force: true }),
+      ])
+    }
   }
 }

@@ -383,6 +388,12 @@ async function processFileOnce(entry, filePath) {
     // know the hash of.
     return entry.hash
   }
+  if (DRY_RUN) {
+    console.log(
+      `DRY-RUN: would process file ${fileId} for project ${projectId}`
+    )
+    return 'dry-run'
+  }
   const blobStore = new BlobStore(historyId)
   STATS.readFromGCSCount++
   // make a fetch request to filestore itself



diff --git a/libraries/logger/logging-manager.js b/libraries/logger/logging-manager.js
index edf922be72b..9fb4f284053 100644
--- a/libraries/logger/logging-manager.js
+++ b/libraries/logger/logging-manager.js
@@ -11,7 +11,7 @@ const LoggingManager = {
   /**
    * @param {string} name - The name of the logger
    */
-  initialize(name) {
+  initialize(name, options = {}) {
     this.isProduction =
       (process.env.NODE_ENV || '').toLowerCase() === 'production'
     const isTest = (process.env.NODE_ENV || '').toLowerCase() === 'test'
@@ -27,7 +27,7 @@ const LoggingManager = {
         req: Serializers.req,
         res: Serializers.res,
       },
-      streams: [this._getOutputStreamConfig()],
+      streams: options.streams ?? [this._getOutputStreamConfig()],
     })
     this._setupRingBuffer()
     this._setupLogLevelChecker()



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 68ce4b67aa2..a7f220ec362 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -79,10 +79,14 @@ ObjectId.cacheHexString = true
  */

 /**
- * @return {{PROJECT_IDS_FROM: string, PROCESS_HASHED_FILES: boolean, LOGGING_IDENTIFIER: string, BATCH_RANGE_START: string, PROCESS_BLOBS: boolean, BATCH_RANGE_END: string, PROCESS_NON_DELETED_PROJECTS: boolean, PROCESS_DELETED_PROJECTS: boolean, DRY_RUN: boolean}}
+ * @return {{PROJECT_IDS_FROM: string, PROCESS_HASHED_FILES: boolean, LOGGING_IDENTIFIER: string, BATCH_RANGE_START: string, PROCESS_BLOBS: boolean, BATCH_RANGE_END: string, PROCESS_NON_DELETED_PROJECTS: boolean, PROCESS_DELETED_PROJECTS: boolean, DRY_RUN: boolean, OUTPUT_FILE: string, PROCESS_BLOBS: boolean}}
  */
 function parseArgs() {
   const PUBLIC_LAUNCH_DATE = new Date('2012-01-01T00:00:00Z')
+  const DEFAULT_OUTPUT_FILE = `file-migration-${new Date()
+    .toISOString()
+    .replace(/[:.]/g, '_')}.log`
+
   const args = commandLineArgs([
     { name: 'projects', type: Boolean },
     { name: 'deleted-projects', type: Boolean },
@@ -90,6 +94,7 @@ function parseArgs() {
     { name: 'skip-existing-blobs', type: Boolean },
     { name: 'from-file', type: String, defaultValue: '' },
     { name: 'dry-run', type: Boolean },
+    { name: 'output', type: String, defaultValue: DEFAULT_OUTPUT_FILE },
     {
       name: 'BATCH_RANGE_START',
       type: String,
@@ -111,6 +116,7 @@ function parseArgs() {
     PROCESS_HASHED_FILES: args['include-hashed-files'],
     PROCESS_BLOBS: !args['skip-existing-blobs'],
     DRY_RUN: args['dry-run'],
+    OUTPUT_FILE: args.output,
     BATCH_RANGE_START,
     BATCH_RANGE_END,
     LOGGING_IDENTIFIER: args['logging-id'] || BATCH_RANGE_START,
@@ -124,6 +130,7 @@ const {
   PROCESS_BLOBS,
   PROCESS_HASHED_FILES,
   DRY_RUN,
+  OUTPUT_FILE,
   BATCH_RANGE_START,
   BATCH_RANGE_END,
   LOGGING_IDENTIFIER,
@@ -158,6 +165,21 @@ const STREAM_HIGH_WATER_MARK = parseInt(
 const LOGGING_INTERVAL = parseInt(process.env.LOGGING_INTERVAL || '60000', 10)
 const SLEEP_BEFORE_EXIT = parseInt(process.env.SLEEP_BEFORE_EXIT || '1000', 10)

+// Log output to a file
+logger.initialize('file-migration', {
+  streams: [
+    {
+      stream:
+        OUTPUT_FILE === '-'
+          ? process.stdout
+          : fs.createWriteStream(OUTPUT_FILE, { flags: 'a' }),
+    },
+  ],
+})
+async function trackProgress(progress) {
+  logger.info({}, progress)
+}
+
 // Filestore endpoint location
 const FILESTORE_HOST = process.env.FILESTORE_HOST || '127.0.0.1'
 const FILESTORE_PORT = process.env.FILESTORE_PORT || '3009'
@@ -525,8 +547,9 @@ async function queueNextBatch(batch, prefix = 'rootFolder.0') {
   const end = renderObjectId(batch[batch.length - 1]._id)
   const deferred = processBatch(batch, prefix)
     .then(() => {
-      console.error(`Actually completed batch ending ${end}`)
+      logger.info({ end }, 'actually completed batch')
     })
+
     .catch(err => {
       logger.error({ err, start, end }, 'fatal error processing batch')
       throw err
@@ -1062,6 +1085,7 @@ async function processNonDeletedProjects() {
       {
         BATCH_RANGE_START,
         BATCH_RANGE_END,
+        trackProgress,
       }
     )
   } catch (err) {
diff --git a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
index 0f8bdbf3e1a..117352d6164 100644
--- a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
+++ b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
@@ -544,6 +544,7 @@ describe('back_fill_file_hash script', function () {
         process.argv0,
         [
           'storage/scripts/back_fill_file_hash.mjs',
+          '--output=-',
           '--projects',
           '--deleted-projects',
           ...args,



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index a7f220ec362..4beba19cf4c 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -88,6 +88,7 @@ function parseArgs() {
     .replace(/[:.]/g, '_')}.log`

   const args = commandLineArgs([
+    { name: 'all', alias: 'a', type: Boolean },
     { name: 'projects', type: Boolean },
     { name: 'deleted-projects', type: Boolean },
     { name: 'include-hashed-files', type: Boolean },
@@ -108,6 +109,36 @@ function parseArgs() {
     { name: 'logging-id', type: String, defaultValue: '' },
   ])

+  // If no arguments are provided, display a usage message
+  if (process.argv.length <= 2) {
+    console.error(
+      'Usage: node back_fill_file_hash.mjs --all | --projects | --deleted-projects'
+    )
+    process.exit(1)
+  }
+
+  // Require at least one of --projects, --deleted-projects and --all
+  if (!args.projects && !args['deleted-projects'] && !args.all) {
+    console.error(
+      'Must specify at least one of --projects and --deleted-projects, or --all'
+    )
+    process.exit(1)
+  }
+
+  // Forbid --all with --projects or --deleted-projects
+  if (args.all && (args.projects || args['deleted-projects'])) {
+    console.error('Cannot use --all with --projects or --deleted-projects')
+    process.exit(1)
+  }
+
+  // The --all option processes all projects, including deleted ones
+  // and checks existing hashed files are present in the blob store.
+  if (args.all) {
+    args.projects = true
+    args['deleted-projects'] = true
+    args['include-hashed-files'] = true
+  }
+
   const BATCH_RANGE_START = objectIdFromInput(args.BATCH_RANGE_START).toString()
   const BATCH_RANGE_END = objectIdFromInput(args.BATCH_RANGE_END).toString()
   return {



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 4beba19cf4c..492c5ad939d 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -88,6 +88,7 @@ function parseArgs() {
     .replace(/[:.]/g, '_')}.log`

   const args = commandLineArgs([
+    { name: 'help', alias: 'h', type: Boolean },
     { name: 'all', alias: 'a', type: Boolean },
     { name: 'projects', type: Boolean },
     { name: 'deleted-projects', type: Boolean },
@@ -117,6 +118,48 @@ function parseArgs() {
     process.exit(1)
   }

+  // If --help is provided, display the help message
+  if (args.help) {
+    console.log(`Usage: node back_fill_file_hash.mjs [options]
+
+Project selection options:
+  --all, -a                  Process all projects, including deleted ones
+  --projects                 Process projects (excluding deleted ones)
+  --deleted-projects         Process deleted projects
+  --from-file <file>         Process selected projects ids from file
+
+File selection options:
+  --include-hashed-files     Process files that already have a hash
+  --skip-existing-blobs      Skip processing files already in the blob store
+
+Logging options:
+  --output <file>            Output log to the specified file
+                             (default: file-migration-<timestamp>.log)
+  --logging-id <id>          Identifier for logging
+                             (default: BATCH_RANGE_START)
+
+Batch range options:
+  --BATCH_RANGE_START <date> Start date for processing
+                             (default: ${args.BATCH_RANGE_START})
+  --BATCH_RANGE_END <date>   End date for processing
+                             (default: ${args.BATCH_RANGE_END})
+
+Other options:
+  --dry-run                  Perform a dry run without making changes
+  --help, -h                 Show this help message
+
+Typical usage:
+
+  node back_fill_file_hash.mjs --all
+
+is equivalent to
+
+  node back_fill_file_hash.mjs --projects --deleted-projects \\
+    --include-hashed-files
+`)
+    process.exit(0)
+  }
+
   // Require at least one of --projects, --deleted-projects and --all
   if (!args.projects && !args['deleted-projects'] && !args.all) {
     console.error(



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 492c5ad939d..b20e365c4ff 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -79,7 +79,7 @@ ObjectId.cacheHexString = true
  */

 /**
- * @return {{PROJECT_IDS_FROM: string, PROCESS_HASHED_FILES: boolean, LOGGING_IDENTIFIER: string, BATCH_RANGE_START: string, PROCESS_BLOBS: boolean, BATCH_RANGE_END: string, PROCESS_NON_DELETED_PROJECTS: boolean, PROCESS_DELETED_PROJECTS: boolean, DRY_RUN: boolean, OUTPUT_FILE: string, PROCESS_BLOBS: boolean}}
+ * @return {{PROJECT_IDS_FROM: string, PROCESS_HASHED_FILES: boolean, LOGGING_IDENTIFIER: string, BATCH_RANGE_START: string, BATCH_RANGE_END: string, PROCESS_NON_DELETED_PROJECTS: boolean, PROCESS_DELETED_PROJECTS: boolean, PROCESS_BLOBS: boolean, DRY_RUN: boolean, OUTPUT_FILE: string, DISPLAY_REPORT: boolean}}
  */
 function parseArgs() {
   const PUBLIC_LAUNCH_DATE = new Date('2012-01-01T00:00:00Z')
@@ -97,6 +97,7 @@ function parseArgs() {
     { name: 'from-file', type: String, defaultValue: '' },
     { name: 'dry-run', type: Boolean },
     { name: 'output', type: String, defaultValue: DEFAULT_OUTPUT_FILE },
+    { name: 'report', type: Boolean },
     {
       name: 'BATCH_RANGE_START',
       type: String,
@@ -145,6 +146,7 @@ Batch range options:
                              (default: ${args.BATCH_RANGE_END})

 Other options:
+  --report                   Display a report of the current status
   --dry-run                  Perform a dry run without making changes
   --help, -h                 Show this help message

@@ -160,10 +162,15 @@ is equivalent to
     process.exit(0)
   }

-  // Require at least one of --projects, --deleted-projects and --all
-  if (!args.projects && !args['deleted-projects'] && !args.all) {
+  // Require at least one of --projects, --deleted-projects and --all or --report
+  if (
+    !args.projects &&
+    !args['deleted-projects'] &&
+    !args.all &&
+    !args.report
+  ) {
     console.error(
-      'Must specify at least one of --projects and --deleted-projects, or --all'
+      'Must specify at least one of --projects and --deleted-projects, --all or --report'
     )
     process.exit(1)
   }
@@ -174,6 +181,14 @@ is equivalent to
     process.exit(1)
   }

+  // Forbid --all, --projects, --deleted-projects with --report
+  if (args.report && (args.all || args.projects || args['deleted-projects'])) {
+    console.error(
+      'Cannot use --report with --all, --projects or --deleted-projects'
+    )
+    process.exit(1)
+  }
+
   // The --all option processes all projects, including deleted ones
   // and checks existing hashed files are present in the blob store.
   if (args.all) {
@@ -195,6 +210,7 @@ is equivalent to
     BATCH_RANGE_END,
     LOGGING_IDENTIFIER: args['logging-id'] || BATCH_RANGE_START,
     PROJECT_IDS_FROM: args['from-file'],
+    DISPLAY_REPORT: args.report,
   }
 }

@@ -209,6 +225,7 @@ const {
   BATCH_RANGE_END,
   LOGGING_IDENTIFIER,
   PROJECT_IDS_FROM,
+  DISPLAY_REPORT,
 } = parseArgs()

 // We need to handle the start and end differently as ids of deleted projects are created at time of deletion.
@@ -254,6 +271,108 @@ async function trackProgress(progress) {
   logger.info({}, progress)
 }

+/**
+ * Display the stats for the projects or deletedProjects collections.
+ *
+ * @param {number} N - Number of samples to take from the collection.
+ * @param {string} name - Name of the collection being sampled.
+ * @param {Collection} collection - MongoDB collection to query.
+ * @param {Object} query - MongoDB query to filter documents.
+ * @param {Object} projection - MongoDB projection to select fields.
+ * @param {number} collectionCount - Total number of documents in the collection.
+ * @returns {Promise<void>} Resolves when stats have been displayed.
+ */
+async function getStatsForCollection(
+  N,
+  name,
+  collection,
+  query,
+  projection,
+  collectionCount
+) {
+  const stats = {
+    projectCount: 0,
+    projectsWithAllHashes: 0,
+    fileCount: 0,
+    fileWithHashCount: 0,
+  }
+  // Pick a random sample of projects and estimate the number of files without hashes
+  const result = await collection
+    .aggregate([
+      { $sample: { size: N } },
+      { $match: query },
+      {
+        $project: projection,
+      },
+    ])
+    .toArray()
+
+  for (const project of result) {
+    const fileTree = JSON.stringify(project, [
+      'rootFolder',
+      'folders',
+      'fileRefs',
+      'hash',
+      '_id',
+    ])
+    // count the number of files without a hash, these are uniquely identified
+    // by entries with {"_id":"...."} since we have filtered the file tree
+    const filesWithoutHash = fileTree.match(/\{"_id":"[0-9a-f]{24}"\}/g) || []
+    // count the number of files with a hash, these are uniquely identified
+    // by the number of "hash" strings due to the filtering
+    const filesWithHash = fileTree.match(/"hash"/g) || []
+    stats.fileCount += filesWithoutHash.length + filesWithHash.length
+    stats.fileWithHashCount += filesWithHash.length
+    stats.projectCount++
+    stats.projectsWithAllHashes += filesWithoutHash.length === 0 ? 1 : 0
+  }
+  console.log(`Sampled stats for ${name}:`)
+  const fractionSampled = stats.projectCount / collectionCount
+  const percentageSampled = (fractionSampled * 100).toFixed(1)
+  const fractionConverted = stats.projectsWithAllHashes / stats.projectCount
+  const percentageConverted = (fractionConverted * 100).toFixed(1)
+  console.log(
+    `- Sampled ${name}: ${stats.projectCount} (${percentageSampled}%)`
+  )
+  console.log(
+    `- Sampled ${name} with all hashes present: ${stats.projectsWithAllHashes}`
+  )
+  console.log(
+    `- Percentage of ${name} converted: ${percentageConverted}% (estimated)`
+  )
+}
+
+/**
+ * Displays a report of the current status of projects and deleted projects,
+ * including counts and estimated progress based on a sample.
+ */
+async function displayReport() {
+  const projectsCountResult = await projectsCollection.countDocuments()
+  const deletedProjectsCountResult =
+    await deletedProjectsCollection.countDocuments()
+  const sampleSize = 1000
+  console.log('Current status:')
+  console.log(`- Projects: ${projectsCountResult}`)
+  console.log(`- Deleted projects: ${deletedProjectsCountResult}`)
+  console.log(`Sampling ${sampleSize} projects to estimate progress...`)
+  await getStatsForCollection(
+    sampleSize,
+    'projects',
+    projectsCollection,
+    { rootFolder: { $exists: true } },
+    { rootFolder: 1 },
+    projectsCountResult
+  )
+  await getStatsForCollection(
+    sampleSize,
+    'deleted projects',
+    deletedProjectsCollection,
+    { 'project.rootFolder': { $exists: true } },
+    { 'project.rootFolder': 1 },
+    deletedProjectsCountResult
+  )
+}
+
 // Filestore endpoint location
 const FILESTORE_HOST = process.env.FILESTORE_HOST || '127.0.0.1'
 const FILESTORE_PORT = process.env.FILESTORE_PORT || '3009'
@@ -1220,6 +1339,12 @@ async function main() {
   console.warn('Done.')
 }

+if (DISPLAY_REPORT) {
+  console.warn('Displaying report...')
+  await displayReport()
+  process.exit(0)
+}
+
 try {
   try {
     await main()



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index b20e365c4ff..2bfc4051622 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -267,8 +267,20 @@ logger.initialize('file-migration', {
     },
   ],
 })
+
+let lastElapsedTime = 0
 async function trackProgress(progress) {
-  logger.info({}, progress)
+  const elapsedTime = Math.floor((performance.now() - processStart) / 1000)
+  if (lastElapsedTime === elapsedTime) {
+    // Avoid spamming the console with the same progress message
+    return
+  }
+  lastElapsedTime = elapsedTime
+  readline.clearLine(process.stdout, 0)
+  readline.cursorTo(process.stdout, 0)
+  process.stdout.write(
+    `Processed ${STATS.projects} projects, elapsed time ${elapsedTime}s`
+  )
 }

 /**
@@ -1287,7 +1299,7 @@ async function processNonDeletedProjects() {
   } finally {
     await waitForDeferredQueues()
   }
-  console.warn('Done updating live projects')
+  console.warn('\nDone updating live projects')
 }

 async function processDeletedProjects() {
@@ -1306,7 +1318,9 @@ async function processDeletedProjects() {
         'project.rootFolder': 1,
         'project._id': 1,
         'project.overleaf.history.id': 1,
-      }
+      },
+      {},
+      { trackProgress }
     )
   } catch (err) {
     gracefulShutdownInitiated = true
@@ -1314,7 +1328,7 @@ async function processDeletedProjects() {
   } finally {
     await waitForDeferredQueues()
   }
-  console.warn('Done updating deleted projects')
+  console.warn('\nDone updating deleted projects')
 }

 async function main() {



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 2bfc4051622..c9fd7d233a7 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -94,9 +94,14 @@ function parseArgs() {
     { name: 'deleted-projects', type: Boolean },
     { name: 'include-hashed-files', type: Boolean },
     { name: 'skip-existing-blobs', type: Boolean },
-    { name: 'from-file', type: String, defaultValue: '' },
-    { name: 'dry-run', type: Boolean },
-    { name: 'output', type: String, defaultValue: DEFAULT_OUTPUT_FILE },
+    { name: 'from-file', alias: 'f', type: String, defaultValue: '' },
+    { name: 'dry-run', alias: 'n', type: Boolean },
+    {
+      name: 'output',
+      alias: 'o',
+      type: String,
+      defaultValue: DEFAULT_OUTPUT_FILE,
+    },
     { name: 'report', type: Boolean },
     {
       name: 'BATCH_RANGE_START',
@@ -127,14 +132,14 @@ Project selection options:
   --all, -a                  Process all projects, including deleted ones
   --projects                 Process projects (excluding deleted ones)
   --deleted-projects         Process deleted projects
-  --from-file <file>         Process selected projects ids from file
+  --from-file <file>, -f <file> Process selected projects ids from file

 File selection options:
   --include-hashed-files     Process files that already have a hash
   --skip-existing-blobs      Skip processing files already in the blob store

 Logging options:
-  --output <file>            Output log to the specified file
+  --output <file>, -o <file> Output log to the specified file
                              (default: file-migration-<timestamp>.log)
   --logging-id <id>          Identifier for logging
                              (default: BATCH_RANGE_START)
@@ -147,7 +152,7 @@ Batch range options:

 Other options:
   --report                   Display a report of the current status
-  --dry-run                  Perform a dry run without making changes
+  --dry-run, -n              Perform a dry run without making changes
   --help, -h                 Show this help message

 Typical usage:



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index c9fd7d233a7..8f28e8a4d78 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -326,6 +326,7 @@ async function getStatsForCollection(

   for (const project of result) {
     const fileTree = JSON.stringify(project, [
+      'project',
       'rootFolder',
       'folders',
       'fileRefs',



diff --git a/libraries/mongo-utils/batchedUpdate.js b/libraries/mongo-utils/batchedUpdate.js
index 41af41f0d4a..f1253c587d3 100644
--- a/libraries/mongo-utils/batchedUpdate.js
+++ b/libraries/mongo-utils/batchedUpdate.js
@@ -35,7 +35,7 @@ let BATCHED_UPDATE_RUNNING = false
  * @property {string} [BATCH_RANGE_START]
  * @property {string} [BATCH_SIZE]
  * @property {string} [VERBOSE_LOGGING]
- * @property {(progress: string) => Promise<void>} [trackProgress]
+ * @property {(progress: string, options?: object) => Promise<void>} [trackProgress]
  */

 /**
@@ -269,9 +269,12 @@ async function batchedUpdate(
           await performUpdate(collection, nextBatch, update)
         }
       }
-      await trackProgress(`Completed batch ending ${renderObjectId(end)}`)
+      await trackProgress(`Completed batch ending ${renderObjectId(end)}`, {
+        completedBatch: true,
+      })
       start = end
     }
+    await trackProgress('Completed all batches', { completedAll: true })
     return updated
   } finally {
     BATCHED_UPDATE_RUNNING = false



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 8f28e8a4d78..2b54fdb1687 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -274,9 +274,16 @@ logger.initialize('file-migration', {
 })

 let lastElapsedTime = 0
-async function trackProgress(progress) {
+async function trackProgress(progress, options = {}) {
+  if (OUTPUT_FILE === '-') {
+    return // skip progress tracking when logging to stdout
+  }
+  if (options.completedAll) {
+    process.stdout.write('\n')
+    return
+  }
   const elapsedTime = Math.floor((performance.now() - processStart) / 1000)
-  if (lastElapsedTime === elapsedTime) {
+  if (lastElapsedTime === elapsedTime && !options.completedBatch) {
     // Avoid spamming the console with the same progress message
     return
   }
@@ -1305,7 +1312,7 @@ async function processNonDeletedProjects() {
   } finally {
     await waitForDeferredQueues()
   }
-  console.warn('\nDone updating live projects')
+  console.warn('Done updating live projects')
 }

 async function processDeletedProjects() {
@@ -1334,7 +1341,7 @@ async function processDeletedProjects() {
   } finally {
     await waitForDeferredQueues()
   }
-  console.warn('\nDone updating deleted projects')
+  console.warn('Done updating deleted projects')
 }

 async function main() {
@@ -1381,7 +1388,9 @@ try {

   let code = 0
   if (STATS.filesFailed > 0) {
-    console.warn('Some files could not be processed, see logs and try again')
+    console.warn(
+      `Some files could not be processed, see logs in ${OUTPUT_FILE} and try again`
+    )
     code++
   }
   if (STATS.fileHardDeleted > 0) {



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 2b54fdb1687..fc46f245d1a 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -525,7 +525,7 @@ function computeDiff(nextEventLoopStats, now) {
 function printStats(isLast = false) {
   const now = performance.now()
   const nextEventLoopStats = performance.eventLoopUtilization()
-  const logLine = JSON.stringify({
+  const logLine = {
     time: new Date(),
     LOGGING_IDENTIFIER,
     ...STATS,
@@ -533,11 +533,11 @@ function printStats(isLast = false) {
     eventLoop: nextEventLoopStats,
     diff: computeDiff(nextEventLoopStats, now),
     deferredBatches: Array.from(deferredBatches.keys()),
-  })
-  if (isLast) {
-    console.warn(logLine)
+  }
+  if (isLast && OUTPUT_FILE === '-') {
+    console.warn(JSON.stringify(logLine))
   } else {
-    console.log(logLine)
+    logger.info(logLine, 'file-migration stats')
   }
   lastEventLoopStats = nextEventLoopStats
   lastLog = Object.assign({}, STATS)



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index fc46f245d1a..4a4d93d902c 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -92,7 +92,7 @@ function parseArgs() {
     { name: 'all', alias: 'a', type: Boolean },
     { name: 'projects', type: Boolean },
     { name: 'deleted-projects', type: Boolean },
-    { name: 'include-hashed-files', type: Boolean },
+    { name: 'skip-hashed-files', type: Boolean },
     { name: 'skip-existing-blobs', type: Boolean },
     { name: 'from-file', alias: 'f', type: String, defaultValue: '' },
     { name: 'dry-run', alias: 'n', type: Boolean },
@@ -135,7 +135,7 @@ Project selection options:
   --from-file <file>, -f <file> Process selected projects ids from file

 File selection options:
-  --include-hashed-files     Process files that already have a hash
+  --skip-hashed-files        Skip processing files that already have a hash
   --skip-existing-blobs      Skip processing files already in the blob store

 Logging options:
@@ -161,8 +161,7 @@ Typical usage:

 is equivalent to

-  node back_fill_file_hash.mjs --projects --deleted-projects \\
-    --include-hashed-files
+  node back_fill_file_hash.mjs --projects --deleted-projects
 `)
     process.exit(0)
   }
@@ -199,7 +198,6 @@ is equivalent to
   if (args.all) {
     args.projects = true
     args['deleted-projects'] = true
-    args['include-hashed-files'] = true
   }

   const BATCH_RANGE_START = objectIdFromInput(args.BATCH_RANGE_START).toString()
@@ -207,7 +205,7 @@ is equivalent to
   return {
     PROCESS_NON_DELETED_PROJECTS: args.projects,
     PROCESS_DELETED_PROJECTS: args['deleted-projects'],
-    PROCESS_HASHED_FILES: args['include-hashed-files'],
+    PROCESS_HASHED_FILES: !args['skip-hashed-files'],
     PROCESS_BLOBS: !args['skip-existing-blobs'],
     DRY_RUN: args['dry-run'],
     OUTPUT_FILE: args.output,
diff --git a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
index 117352d6164..a95bcbabd7e 100644
--- a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
+++ b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
@@ -855,7 +855,7 @@ describe('back_fill_file_hash script', function () {
     // Practically, this is slow and moving it to the end of the tests gets us there most of the way.
     it('should process nothing on re-run', async function () {
       const rerun = await runScript(
-        processHashedFiles ? ['--include-hashed-files'] : [],
+        !processHashedFiles ? ['--skip-hashed-files'] : [],
         {},
         false
       )
@@ -981,7 +981,7 @@ describe('back_fill_file_hash script', function () {
     it('should gracefully handle fatal errors', async function () {
       mockFilestore.deleteObject(projectId0, fileId0)
       const t0 = Date.now()
-      const { stats, result } = await tryRunScript([], {
+      const { stats, result } = await tryRunScript(['--skip-hashed-files'], {
         RETRIES: '10',
         RETRY_DELAY_MS: '1000',
       })
@@ -1016,7 +1016,7 @@ describe('back_fill_file_hash script', function () {
           value: { stats, result },
         },
       ] = await Promise.allSettled([
-        tryRunScript([], {
+        tryRunScript(['--skip-hashed-files'], {
           RETRY_DELAY_MS: '100',
           RETRIES: '60',
           RETRY_FILESTORE_404: 'true', // 404s are the easiest to simulate in tests
@@ -1042,7 +1042,7 @@ describe('back_fill_file_hash script', function () {
     let output
     before('prepare environment', prepareEnvironment)
     before('run script', async function () {
-      output = await runScript([], {
+      output = await runScript(['--skip-hashed-files'], {
         CONCURRENCY: '1',
       })
     })
@@ -1111,10 +1111,10 @@ describe('back_fill_file_hash script', function () {
     let output1, output2
     before('prepare environment', prepareEnvironment)
     before('run script without hashed files', async function () {
-      output1 = await runScript([], {})
+      output1 = await runScript(['--skip-hashed-files'], {})
     })
     before('run script with hashed files', async function () {
-      output2 = await runScript(['--include-hashed-files'], {})
+      output2 = await runScript([], {})
     })
     it('should print stats for the first run without hashed files', function () {
       expect(output1.stats).deep.equal(STATS_ALL)
@@ -1134,7 +1134,7 @@ describe('back_fill_file_hash script', function () {
     let output
     before('prepare environment', prepareEnvironment)
     before('run script', async function () {
-      output = await runScript([], {
+      output = await runScript(['--skip-hashed-files'], {
         CONCURRENCY: '10',
       })
     })
@@ -1148,7 +1148,7 @@ describe('back_fill_file_hash script', function () {
     let output
     before('prepare environment', prepareEnvironment)
     before('run script', async function () {
-      output = await runScript([], {
+      output = await runScript(['--skip-hashed-files'], {
         STREAM_HIGH_WATER_MARK: (1024 * 1024).toString(),
       })
     })
@@ -1162,7 +1162,7 @@ describe('back_fill_file_hash script', function () {
     let output
     before('prepare environment', prepareEnvironment)
     before('run script', async function () {
-      output = await runScript(['--include-hashed-files'], {})
+      output = await runScript([], {})
     })
     it('should print stats', function () {
       expect(output.stats).deep.equal(
@@ -1191,7 +1191,7 @@ describe('back_fill_file_hash script', function () {
     })
     let output
     before('run script', async function () {
-      output = await runScript([], {
+      output = await runScript(['--skip-hashed-files'], {
         CONCURRENCY: '1',
       })
     })
@@ -1212,14 +1212,20 @@ describe('back_fill_file_hash script', function () {
     let outputPart0, outputPart1
     before('prepare environment', prepareEnvironment)
     before('run script on part 0', async function () {
-      outputPart0 = await runScript([`--BATCH_RANGE_END=${edge}`], {
-        CONCURRENCY: '1',
-      })
+      outputPart0 = await runScript(
+        ['--skip-hashed-files', `--BATCH_RANGE_END=${edge}`],
+        {
+          CONCURRENCY: '1',
+        }
+      )
     })
     before('run script on part 1', async function () {
-      outputPart1 = await runScript([`--BATCH_RANGE_START=${edge}`], {
-        CONCURRENCY: '1',
-      })
+      outputPart1 = await runScript(
+        ['--skip-hashed-files', `--BATCH_RANGE_START=${edge}`],
+        {
+          CONCURRENCY: '1',
+        }
+      )
     })

     it('should print stats for part 0', function () {
@@ -1264,10 +1270,16 @@ describe('back_fill_file_hash script', function () {

     let outputPart0, outputPart1
     before('run script on part 0', async function () {
-      outputPart0 = await runScript([`--from-file=${path0}`])
+      outputPart0 = await runScript([
+        '--skip-hashed-files',
+        `--from-file=${path0}`,
+      ])
     })
     before('run script on part 1', async function () {
-      outputPart1 = await runScript([`--from-file=${path1}`])
+      outputPart1 = await runScript([
+        '--skip-hashed-files',
+        `--from-file=${path1}`,
+      ])
     })

     /**



diff --git a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
index a95bcbabd7e..fc6941bd7bb 100644
--- a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
+++ b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
@@ -975,7 +975,7 @@ describe('back_fill_file_hash script', function () {
     STATS_UP_FROM_PROJECT1_ONWARD
   )

-  describe('error cases', () => {
+  describe('error cases', function () {
     beforeEach('prepare environment', prepareEnvironment)

     it('should gracefully handle fatal errors', async function () {
@@ -1237,7 +1237,7 @@ describe('back_fill_file_hash script', function () {
     commonAssertions()
   })

-  describe('projectIds from file', () => {
+  describe('projectIds from file', function () {
     const path0 = '/tmp/project-ids-0.txt'
     const path1 = '/tmp/project-ids-1.txt'
     before('prepare environment', prepareEnvironment)



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 4a4d93d902c..375e582c331 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -555,7 +555,7 @@ function handleSignal() {

 /**
  * @param {QueueEntry} entry
- * @return {Promise<string>}
+ * @return {Promise<string|undefined>}
  */
 async function processFileWithCleanup(entry) {
   const {
@@ -578,7 +578,7 @@ async function processFileWithCleanup(entry) {
 /**
  * @param {QueueEntry} entry
  * @param {string} filePath
- * @return {Promise<string>}
+ * @return {Promise<string|undefined>}
  */
 async function processFile(entry, filePath) {
   for (let attempt = 0; attempt < RETRIES; attempt++) {
@@ -612,7 +612,7 @@ async function processFile(entry, filePath) {
 /**
  * @param {QueueEntry} entry
  * @param {string} filePath
- * @return {Promise<string>}
+ * @return {Promise<string|undefined>}
  */
 async function processFileOnce(entry, filePath) {
   const {
@@ -627,10 +627,7 @@ async function processFileOnce(entry, filePath) {
     return entry.hash
   }
   if (DRY_RUN) {
-    console.log(
-      `DRY-RUN: would process file ${fileId} for project ${projectId}`
-    )
-    return 'dry-run'
+    return // skip processing in dry-run mode by returning undefined
   }
   const blobStore = new BlobStore(historyId)
   STATS.readFromGCSCount++
@@ -843,6 +840,9 @@ async function handleDeletedFileTreeBatch(batch) {
  * @return {Promise<boolean>}
  */
 async function tryUpdateFileRefInMongo(entry) {
+  if (DRY_RUN) {
+    return true // skip mongo updates in dry-run mode
+  }
   if (entry.path.startsWith('project.')) {
     return await tryUpdateFileRefInMongoInDeletedProject(entry)
   }
@@ -865,6 +865,9 @@ async function tryUpdateFileRefInMongo(entry) {
  * @return {Promise<boolean>}
  */
 async function tryUpdateFileRefInMongoInDeletedProject(entry) {
+  if (DRY_RUN) {
+    return true // skip mongo updates in dry-run mode
+  }
   STATS.mongoUpdates++
   const result = await deletedProjectsCollection.updateOne(
     {
@@ -1165,6 +1168,7 @@ class ProjectContext {
    */
   async #tryBatchHashWrites(collection, entries, query) {
     if (entries.length === 0) return []
+    if (DRY_RUN) return [] // skip mongo updates in dry-run mode
     const update = {}
     for (const entry of entries) {
       query[`${entry.path}._id`] = new ObjectId(entry.fileId)
@@ -1210,7 +1214,7 @@ class ProjectContext {
     }
   }

-  /** @type {Map<string, Promise<string>>} */
+  /** @type {Map<string, Promise<string|undefined>>} */
   #pendingFiles = new Map()

   /**
@@ -1223,7 +1227,12 @@ class ProjectContext {
       this.#pendingFiles.set(entry.cacheKey, processFileWithCleanup(entry))
     }
     try {
-      entry.hash = await this.#pendingFiles.get(entry.cacheKey)
+      const hash = await this.#pendingFiles.get(entry.cacheKey)
+      if (!hash) {
+        return // hash is undefined in dry-run mode
+      } else {
+        entry.hash = hash
+      }
     } finally {
       this.remainingQueueEntries--
     }
diff --git a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
index fc6941bd7bb..646e75e2b58 100644
--- a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
+++ b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
@@ -1130,6 +1130,45 @@ describe('back_fill_file_hash script', function () {
     commonAssertions(true)
   })

+  describe('full run in dry-run mode', function () {
+    let output
+    before('prepare environment', prepareEnvironment)
+    before('run script', async function () {
+      output = await runScript(
+        ['--dry-run'],
+        {
+          CONCURRENCY: '1',
+        },
+        false
+      )
+    })
+
+    it('should print stats for dry-run mode', function () {
+      // Compute the stats for running the script without dry-run mode.
+      const originalStats = sumStats(STATS_ALL, {
+        ...STATS_FILES_HASHED_EXTRA,
+        readFromGCSCount: 30,
+        readFromGCSIngress: 72,
+        mongoUpdates: 0,
+        filesWithHash: 3,
+      })
+      // For a dry-run mode, we expect the stats to be zero except for the
+      // count of projects, blobs, bad file trees, duplicated files
+      // and files with/without hash.  All the other stats such as mongoUpdates
+      // and writeToGCSCount, etc should be zero.
+      const expectedDryRunStats = {
+        ...STATS_ALL_ZERO,
+        projects: originalStats.projects,
+        blobs: originalStats.blobs,
+        badFileTrees: originalStats.badFileTrees,
+        filesDuplicated: originalStats.filesDuplicated,
+        filesWithHash: originalStats.filesWithHash,
+        filesWithoutHash: originalStats.filesWithoutHash,
+      }
+      expect(output.stats).deep.equal(expectedDryRunStats)
+    })
+  })
+
   describe('full run CONCURRENCY=10', function () {
     let output
     before('prepare environment', prepareEnvironment)



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 375e582c331..85920bcf03a 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -94,7 +94,7 @@ function parseArgs() {
     { name: 'deleted-projects', type: Boolean },
     { name: 'skip-hashed-files', type: Boolean },
     { name: 'skip-existing-blobs', type: Boolean },
-    { name: 'from-file', alias: 'f', type: String, defaultValue: '' },
+    { name: 'from-file', type: String, defaultValue: '' },
     { name: 'dry-run', alias: 'n', type: Boolean },
     {
       name: 'output',
@@ -132,7 +132,7 @@ Project selection options:
   --all, -a                  Process all projects, including deleted ones
   --projects                 Process projects (excluding deleted ones)
   --deleted-projects         Process deleted projects
-  --from-file <file>, -f <file> Process selected projects ids from file
+  --from-file <file>         Process selected projects ids from file

 File selection options:
   --skip-hashed-files        Skip processing files that already have a hash



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 85920bcf03a..092b8f04e43 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -567,10 +567,7 @@ async function processFileWithCleanup(entry) {
     return await processFile(entry, filePath)
   } finally {
     if (!DRY_RUN) {
-      await Promise.all([
-        fs.promises.rm(filePath, { force: true }),
-        fs.promises.rm(filePath + GZ_SUFFIX, { force: true }),
-      ])
+      await fs.promises.rm(filePath, { force: true })
     }
   }
 }
@@ -697,8 +694,6 @@ async function uploadBlobToGCS(blobStore, entry, blob, hash, filePath) {
   entry.ctx.recordHistoryBlob(blob)
 }

-const GZ_SUFFIX = '.gz'
-
 /**
  * @param {Array<QueueEntry>} files
  * @return {Promise<void>}



diff --git a/libraries/mongo-utils/batchedUpdate.js b/libraries/mongo-utils/batchedUpdate.js
index f1253c587d3..41af41f0d4a 100644
--- a/libraries/mongo-utils/batchedUpdate.js
+++ b/libraries/mongo-utils/batchedUpdate.js
@@ -35,7 +35,7 @@ let BATCHED_UPDATE_RUNNING = false
  * @property {string} [BATCH_RANGE_START]
  * @property {string} [BATCH_SIZE]
  * @property {string} [VERBOSE_LOGGING]
- * @property {(progress: string, options?: object) => Promise<void>} [trackProgress]
+ * @property {(progress: string) => Promise<void>} [trackProgress]
  */

 /**
@@ -269,12 +269,9 @@ async function batchedUpdate(
           await performUpdate(collection, nextBatch, update)
         }
       }
-      await trackProgress(`Completed batch ending ${renderObjectId(end)}`, {
-        completedBatch: true,
-      })
+      await trackProgress(`Completed batch ending ${renderObjectId(end)}`)
       start = end
     }
-    await trackProgress('Completed all batches', { completedAll: true })
     return updated
   } finally {
     BATCHED_UPDATE_RUNNING = false
diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 092b8f04e43..755443adf52 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -1305,7 +1305,7 @@ async function processNonDeletedProjects() {
       {
         BATCH_RANGE_START,
         BATCH_RANGE_END,
-        trackProgress,
+        trackProgress: async message => {},
       }
     )
   } catch (err) {
@@ -1335,7 +1335,7 @@ async function processDeletedProjects() {
         'project.overleaf.history.id': 1,
       },
       {},
-      { trackProgress }
+      { trackProgress: async message => {} }
     )
   } catch (err) {
     gracefulShutdownInitiated = true



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 755443adf52..4ca17ddf694 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -272,7 +272,7 @@ logger.initialize('file-migration', {
 })

 let lastElapsedTime = 0
-async function trackProgress(progress, options = {}) {
+async function displayProgress(options = {}) {
   if (OUTPUT_FILE === '-') {
     return // skip progress tracking when logging to stdout
   }
@@ -733,6 +733,7 @@ async function waitForDeferredQueues() {
   // Wait for ALL pending batches to finish, especially wait for their mongo
   // writes to finish to avoid extra work when resuming the batch.
   const all = await Promise.allSettled(deferredBatches.values())
+  displayProgress({ completedAll: true })
   // Now that all batches finished, we can throw if needed.
   for (const res of all) {
     if (res.status === 'rejected') {
@@ -756,6 +757,7 @@ async function queueNextBatch(batch, prefix = 'rootFolder.0') {
   const deferred = processBatch(batch, prefix)
     .then(() => {
       logger.info({ end }, 'actually completed batch')
+      displayProgress({ completedBatch: true })
     })

     .catch(err => {



diff --git a/services/history-v1/storage/scripts/back_fill_file_hash.mjs b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
index 4ca17ddf694..8664be21fbe 100644
--- a/services/history-v1/storage/scripts/back_fill_file_hash.mjs
+++ b/services/history-v1/storage/scripts/back_fill_file_hash.mjs
@@ -1226,7 +1226,11 @@ class ProjectContext {
     try {
       const hash = await this.#pendingFiles.get(entry.cacheKey)
       if (!hash) {
-        return // hash is undefined in dry-run mode
+        if (DRY_RUN) {
+          return // hash is undefined in dry-run mode
+        } else {
+          throw new Error('undefined hash outside dry-run mode')
+        }
       } else {
         entry.hash = hash
       }



diff --git a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
index 646e75e2b58..43884adbe8f 100644
--- a/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
+++ b/services/history-v1/test/acceptance/js/storage/back_fill_file_hash.test.mjs
@@ -1132,7 +1132,15 @@ describe('back_fill_file_hash script', function () {

   describe('full run in dry-run mode', function () {
     let output
+    let projectRecordsBefore
+    let deletedProjectRecordsBefore
     before('prepare environment', prepareEnvironment)
+    before(async function () {
+      projectRecordsBefore = await projectsCollection.find({}).toArray()
+      deletedProjectRecordsBefore = await deletedProjectsCollection
+        .find({})
+        .toArray()
+    })
     before('run script', async function () {
       output = await runScript(
         ['--dry-run'],
@@ -1167,6 +1175,14 @@ describe('back_fill_file_hash script', function () {
       }
       expect(output.stats).deep.equal(expectedDryRunStats)
     })
+    it('should not update mongo', async function () {
+      expect(await projectsCollection.find({}).toArray()).to.deep.equal(
+        projectRecordsBefore
+      )
+      expect(await deletedProjectsCollection.find({}).toArray()).to.deep.equal(
+        deletedProjectRecordsBefore
+      )
+    })
   })

   describe('full run CONCURRENCY=10', function () {