diff --git a/services/document-updater/app/coffee/LockManager.coffee b/services/document-updater/app/coffee/LockManager.coffee
index 37cbe49914..d918dc4332 100644
--- a/services/document-updater/app/coffee/LockManager.coffee
+++ b/services/document-updater/app/coffee/LockManager.coffee
@@ -7,6 +7,8 @@ logger = require "logger-sharelatex"
 os = require "os"
 crypto = require "crypto"
 
+Profiler = require "./Profiler"
+
 HOST = os.hostname()
 PID = process.pid
 RND = crypto.randomBytes(4).toString('hex')
@@ -30,28 +32,34 @@ module.exports = LockManager =
 	tryLock : (doc_id, callback = (err, isFree)->)->
 		lockValue = LockManager.randomLock()
 		key = keys.blockingKey(doc_id:doc_id)
+		profile = new Profiler("tryLock", {doc_id, key, lockValue})
 		rclient.set key, lockValue, "EX", @LOCK_TTL, "NX", (err, gotLock)->
 			return callback(err) if err?
 			if gotLock == "OK"
 				metrics.inc "doc-not-blocking"
+				profile.log("got lock").end()
 				callback err, true, lockValue
 			else
 				metrics.inc "doc-blocking"
-				logger.log {doc_id}, "doc is locked"
+				profile.log("doc is locked").end()
 				callback err, false
 
 	getLock: (doc_id, callback = (error, lockValue) ->) ->
 		startTime = Date.now()
 		testInterval = LockManager.LOCK_TEST_INTERVAL
+		profile = new Profiler("getLock", {doc_id})
 		do attempt = () ->
 			if Date.now() - startTime > LockManager.MAX_LOCK_WAIT_TIME
 				e = new Error("Timeout")
 				e.doc_id = doc_id
+				profile.log("timeout").end()
 				return callback(e)
 
 			LockManager.tryLock doc_id, (error, gotLock, lockValue) ->
 				return callback(error) if error?
+				profile.log("tryLock")
 				if gotLock
+					profile.end()
 					callback(null, lockValue)
 				else
 					setTimeout attempt, testInterval
@@ -72,10 +80,14 @@ module.exports = LockManager =
 
 	releaseLock: (doc_id, lockValue, callback)->
 		key = keys.blockingKey(doc_id:doc_id)
+		profile = new Profiler("releaseLock", {doc_id, key, lockValue})
 		rclient.eval LockManager.unlockScript, 1, key, lockValue, (err, result) ->
 			if err?
 				return callback(err)
-			if result? and result isnt 1 # successful unlock should release exactly one key
-				logger.error {doc_id:doc_id, lockValue:lockValue, redis_err:err, redis_result:result}, "unlocking error"
+			else if result? and result isnt 1 # successful unlock should release exactly one key
+				profile.log("unlockScript:expired-lock").end()
+				logger.error {doc_id:doc_id, key:key, lockValue:lockValue, redis_err:err, redis_result:result}, "unlocking error"
 				return callback(new Error("tried to release timed out lock"))
-			callback(err,result)
+			else
+				profile.log("unlockScript:ok").end()
+				callback(err,result)
diff --git a/services/document-updater/app/coffee/Profiler.coffee b/services/document-updater/app/coffee/Profiler.coffee
new file mode 100644
index 0000000000..dc88345334
--- /dev/null
+++ b/services/document-updater/app/coffee/Profiler.coffee
@@ -0,0 +1,33 @@
+Settings = require('settings-sharelatex')
+logger = require('logger-sharelatex')
+
+deltaMs = (ta, tb) ->
+	nanoSeconds = (ta[0]-tb[0])*1e9 + (ta[1]-tb[1])
+	milliSeconds = Math.floor(nanoSeconds*1e-6)
+	return milliSeconds
+
+module.exports = class Profiler
+	LOG_CUTOFF_TIME: 1000
+
+	constructor: (@name, @args) ->
+		@t0 = @t = process.hrtime()
+		@start = new Date()
+		@updateTimes = []
+
+	log: (label) ->
+		t1 = process.hrtime()
+		dtMilliSec = deltaMs(t1, @t)
+		@t = t1
+		@updateTimes.push [label, dtMilliSec] # timings in ms
+		return @ # make it chainable
+
+	end: (message) ->
+		totalTime = deltaMs(@t, @t0)
+		return if totalTime < @LOG_CUTOFF_TIME # skip anything less than cutoff
+		args = {}
+		for k,v of @args
+			args[k] = v
+		args.updateTimes = @updateTimes
+		args.start = @start
+		args.end = new Date()
+		logger.log args, @name
diff --git a/services/document-updater/app/coffee/UpdateManager.coffee b/services/document-updater/app/coffee/UpdateManager.coffee
index 269b16ee67..70caaf1e03 100644
--- a/services/document-updater/app/coffee/UpdateManager.coffee
+++ b/services/document-updater/app/coffee/UpdateManager.coffee
@@ -10,6 +10,7 @@ Metrics = require "./Metrics"
 Errors = require "./Errors"
 DocumentManager = require "./DocumentManager"
 RangesManager = require "./RangesManager"
+Profiler = require "./Profiler"
 
 module.exports = UpdateManager =
 	processOutstandingUpdates: (project_id, doc_id, callback = (error) ->) ->
@@ -20,13 +21,17 @@ module.exports = UpdateManager =
 			callback()
 
 	processOutstandingUpdatesWithLock: (project_id, doc_id, callback = (error) ->) ->
+		profile = new Profiler("processOutstandingUpdatesWithLock", {project_id, doc_id})
 		LockManager.tryLock doc_id, (error, gotLock, lockValue) =>
 			return callback(error) if error?
 			return callback() if !gotLock
+			profile.log("tryLock")
 			UpdateManager.processOutstandingUpdates project_id, doc_id, (error) ->
 				return UpdateManager._handleErrorInsideLock(doc_id, lockValue, error, callback) if error?
+				profile.log("processOutstandingUpdates")
 				LockManager.releaseLock doc_id, lockValue, (error) =>
 					return callback(error) if error?
+					profile.log("releaseLock").end()
 					UpdateManager.continueProcessingUpdatesWithLock project_id, doc_id, callback
 
 	continueProcessingUpdatesWithLock: (project_id, doc_id, callback = (error) ->) ->
@@ -38,13 +43,20 @@ module.exports = UpdateManager =
 				callback()
 
 	fetchAndApplyUpdates: (project_id, doc_id, callback = (error) ->) ->
+		profile = new Profiler("fetchAndApplyUpdates", {project_id, doc_id})
 		RealTimeRedisManager.getPendingUpdatesForDoc doc_id, (error, updates) =>
 			return callback(error) if error?
 			if updates.length == 0
 				return callback()
-			async.eachSeries updates,
-				(update, cb) -> UpdateManager.applyUpdate project_id, doc_id, update, cb
-				callback
+			profile.log("getPendingUpdatesForDoc")
+			doUpdate = (update, cb)->
+				UpdateManager.applyUpdate project_id, doc_id, update, (err) ->
+					profile.log("applyUpdate")
+					cb(err)
+			finalCallback = (err) ->
+				profile.log("async done").end()
+				callback(err)
+			async.eachSeries updates, doUpdate, finalCallback
 
 	applyUpdate: (project_id, doc_id, update, _callback = (error) ->) ->
 		callback = (error) ->
@@ -66,14 +78,19 @@ module.exports = UpdateManager =
 						HistoryManager.recordAndFlushHistoryOps project_id, doc_id, appliedOps, historyOpsLength, callback
 
 	lockUpdatesAndDo: (method, project_id, doc_id, args..., callback) ->
+		profile = new Profiler("lockUpdatesAndDo", {project_id, doc_id})
 		LockManager.getLock doc_id, (error, lockValue) ->
+			profile.log("getLock")
 			return callback(error) if error?
 			UpdateManager.processOutstandingUpdates project_id, doc_id, (error) ->
 				return UpdateManager._handleErrorInsideLock(doc_id, lockValue, error, callback) if error?
+				profile.log("processOutStandingUpdates")
 				method project_id, doc_id, args..., (error, response_args...) ->
 					return UpdateManager._handleErrorInsideLock(doc_id, lockValue, error, callback) if error?
+					profile.log("method")
 					LockManager.releaseLock doc_id, lockValue, (error) ->
 						return callback(error) if error?
+						profile.log("releaseLock").end()
 						callback null, response_args...
 						# We held the lock for a while so updates might have queued up
 						UpdateManager.continueProcessingUpdatesWithLock project_id, doc_id