diff --git a/Gopkg.lock b/Gopkg.lock
index ec585720..8fc30309 100644
--- a/Gopkg.lock
+++ b/Gopkg.lock
@@ -309,6 +309,20 @@
   revision = "24acd523c756fd9728824cdfac66aad9d8982fb7"
   version = "v2.2.0"
 
+[[projects]]
+  digest = "1:4b08116de0de75c041bb341686f0b139930f26cb84dfdf7641d435548114181d"
+  name = "github.com/globalsign/mgo"
+  packages = [
+    ".",
+    "bson",
+    "internal/json",
+    "internal/sasl",
+    "internal/scram",
+  ]
+  pruneopts = "UT"
+  revision = "113d3961e7311526535a1ef7042196563d442761"
+  version = "r2018.06.15"
+
 [[projects]]
   digest = "1:4afe9b10ebaf13d77f8bad44b2af5a55c17699b375601a6383a671b0713845b9"
   name = "github.com/go-ini/ini"
@@ -943,20 +957,6 @@
   revision = "41344da2231b913fa3d983840a57a6b1b7b631a1"
   version = "v1.12.0"
 
-[[projects]]
-  branch = "v2"
-  digest = "1:5052389c6c809eeced44ec24ff9958bfea70b9859b7a25061c6fd9086c8f8989"
-  name = "gopkg.in/mgo.v2"
-  packages = [
-    ".",
-    "bson",
-    "internal/json",
-    "internal/sasl",
-    "internal/scram",
-  ]
-  pruneopts = "UT"
-  revision = "3f83fa5005286a7fe593b055f0d7771a7dce4655"
-
 [[projects]]
   digest = "1:418363915247a800f7449c1b43b983cbf99c9bd8b8c5094e68f509543437dc9f"
   name = "gopkg.in/olivere/elastic.v5"
@@ -1009,6 +1009,8 @@
     "github.com/getlantern/deepcopy",
     "github.com/ghodss/yaml",
     "github.com/gizak/termui",
+    "github.com/globalsign/mgo",
+    "github.com/globalsign/mgo/bson",
     "github.com/go-test/deep",
     "github.com/golang/gddo/httputil",
     "github.com/golang/protobuf/jsonpb",
@@ -1050,8 +1052,6 @@
     "google.golang.org/grpc/grpclog",
     "google.golang.org/grpc/metadata",
     "google.golang.org/grpc/status",
-    "gopkg.in/mgo.v2",
-    "gopkg.in/mgo.v2/bson",
     "gopkg.in/olivere/elastic.v5",
   ]
   solver-name = "gps-cdcl"
diff --git a/Gopkg.toml b/Gopkg.toml
index 511a1f3c..57a7388c 100644
--- a/Gopkg.toml
+++ b/Gopkg.toml
@@ -174,8 +174,8 @@
   version = "1.12.0"
 
 [[constraint]]
-  branch = "v2"
-  name = "gopkg.in/mgo.v2"
+  version = "r2018.06.15"
+  name = "github.com/globalsign/mgo"
 
 [[constraint]]
   name = "gopkg.in/olivere/elastic.v5"
diff --git a/database/mongodb/counts.go b/database/mongodb/counts.go
index bc784e4e..d6ccf6e9 100644
--- a/database/mongodb/counts.go
+++ b/database/mongodb/counts.go
@@ -3,8 +3,8 @@ package mongodb
 import (
 	"context"
 
+	"github.com/globalsign/mgo/bson"
 	"github.com/ohsu-comp-bio/funnel/tes"
-	"gopkg.in/mgo.v2/bson"
 )
 
 type stateCount struct {
@@ -14,7 +14,10 @@ type stateCount struct {
 
 // TaskStateCounts returns the number of tasks in each state.
 func (db *MongoDB) TaskStateCounts(ctx context.Context) (map[string]int32, error) {
-	pipe := db.tasks.Pipe([]bson.M{
+	sess := db.sess.Copy()
+	defer sess.Close()
+
+	pipe := db.tasks(sess).Pipe([]bson.M{
 		{"$group": bson.M{"_id": "$state", "count": bson.M{"$sum": 1}}},
 	})
 
diff --git a/database/mongodb/events.go b/database/mongodb/events.go
index b7df2420..0ddd1f04 100644
--- a/database/mongodb/events.go
+++ b/database/mongodb/events.go
@@ -5,15 +5,19 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/globalsign/mgo"
+	"github.com/globalsign/mgo/bson"
 	"github.com/ohsu-comp-bio/funnel/events"
 	"github.com/ohsu-comp-bio/funnel/tes"
 	"github.com/ohsu-comp-bio/funnel/util"
-	"gopkg.in/mgo.v2"
-	"gopkg.in/mgo.v2/bson"
 )
 
 // WriteEvent creates an event for the server to handle.
 func (db *MongoDB) WriteEvent(ctx context.Context, req *events.Event) error {
+	sess := db.sess.Copy()
+	defer sess.Close()
+	tasks := db.tasks(sess)
+
 	update := bson.M{}
 	selector := bson.M{"id": req.Id}
 
@@ -25,7 +29,7 @@ func (db *MongoDB) WriteEvent(ctx context.Context, req *events.Event) error {
 				Logs: []*tes.ExecutorLog{},
 			},
 		}
-		return db.tasks.Insert(&task)
+		return tasks.Insert(&task)
 
 	case events.Type_TASK_STATE:
 		retrier := util.NewRetrier()
@@ -39,7 +43,7 @@ func (db *MongoDB) WriteEvent(ctx context.Context, req *events.Event) error {
 		return retrier.Retry(ctx, func() error {
 			// get current state & version
 			current := make(map[string]interface{})
-			q := db.tasks.Find(bson.M{"id": req.Id}).Select(bson.M{"state": 1, "version": 1})
+			q := tasks.Find(bson.M{"id": req.Id}).Select(bson.M{"state": 1, "version": 1})
 			err := q.One(&current)
 			if err == mgo.ErrNotFound {
 				return tes.ErrNotFound
@@ -58,7 +62,7 @@ func (db *MongoDB) WriteEvent(ctx context.Context, req *events.Event) error {
 			// apply version restriction and set update
 			selector["version"] = current["version"]
 			update = bson.M{"$set": bson.M{"state": to, "version": time.Now().UnixNano()}}
-			return db.tasks.Update(selector, update)
+			return tasks.Update(selector, update)
 		})
 
 	case events.Type_TASK_START_TIME:
@@ -132,5 +136,5 @@ func (db *MongoDB) WriteEvent(ctx context.Context, req *events.Event) error {
 		}
 	}
 
-	return db.tasks.Update(selector, update)
+	return tasks.Update(selector, update)
 }
diff --git a/database/mongodb/new.go b/database/mongodb/new.go
index 63711bb4..713f24df 100644
--- a/database/mongodb/new.go
+++ b/database/mongodb/new.go
@@ -4,46 +4,56 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/globalsign/mgo"
 	"github.com/ohsu-comp-bio/funnel/config"
-	"gopkg.in/mgo.v2"
 )
 
 // MongoDB provides an MongoDB database server backend.
 type MongoDB struct {
-	sess  *mgo.Session
-	conf  config.MongoDB
-	tasks *mgo.Collection
-	nodes *mgo.Collection
-	// events  *mgo.Collection
+	sess *mgo.Session
+	conf config.MongoDB
 }
 
 // NewMongoDB returns a new MongoDB instance.
 func NewMongoDB(conf config.MongoDB) (*MongoDB, error) {
 	sess, err := mgo.DialWithInfo(&mgo.DialInfo{
-		Addrs:    conf.Addrs,
-		Username: conf.Username,
-		Password: conf.Password,
-		Database: conf.Database,
-		Timeout:  time.Duration(conf.Timeout),
-		// DialServer: func(addr *mgo.ServerAddr) (net.Conn, error) {
-		// 	return tls.Dial("tcp", addr.String(), &tls.Config{})
-		// },
+		Addrs:         conf.Addrs,
+		Username:      conf.Username,
+		Password:      conf.Password,
+		Database:      conf.Database,
+		Timeout:       time.Duration(conf.Timeout),
+		AppName:       "funnel",
+		PoolLimit:     4096,
+		PoolTimeout:   0, // wait for connection to become available
+		MinPoolSize:   10,
+		MaxIdleTimeMS: 120000, // 2 min
 	})
 	if err != nil {
 		return nil, err
 	}
 	db := &MongoDB{
-		sess:  sess,
-		conf:  conf,
-		tasks: sess.DB(conf.Database).C("tasks"),
-		nodes: sess.DB(conf.Database).C("nodes"),
+		sess: sess,
+		conf: conf,
 	}
 	return db, nil
 }
 
+func (db *MongoDB) tasks(sess *mgo.Session) *mgo.Collection {
+	return sess.DB(db.conf.Database).C("tasks")
+}
+
+func (db *MongoDB) nodes(sess *mgo.Session) *mgo.Collection {
+	return sess.DB(db.conf.Database).C("nodes")
+}
+
 // Init creates tables in MongoDB.
 func (db *MongoDB) Init() error {
-	names, err := db.sess.DB(db.conf.Database).CollectionNames()
+	sess := db.sess.Copy()
+	defer sess.Close()
+	tasks := db.tasks(sess)
+	nodes := db.nodes(sess)
+
+	names, err := sess.DB(db.conf.Database).CollectionNames()
 	if err != nil {
 		return fmt.Errorf("error listing collection names in database %s: %v", db.conf.Database, err)
 	}
@@ -59,12 +69,12 @@ func (db *MongoDB) Init() error {
 	}
 
 	if !tasksFound {
-		err = db.tasks.Create(&mgo.CollectionInfo{})
+		err = tasks.Create(&mgo.CollectionInfo{})
 		if err != nil {
 			return fmt.Errorf("error creating tasks collection in database %s: %v", db.conf.Database, err)
 		}
 
-		err = db.tasks.EnsureIndex(mgo.Index{
+		err = tasks.EnsureIndex(mgo.Index{
 			Key:        []string{"-id", "-creationtime"},
 			Unique:     true,
 			DropDups:   true,
@@ -77,12 +87,12 @@ func (db *MongoDB) Init() error {
 	}
 
 	if !nodesFound {
-		err = db.nodes.Create(&mgo.CollectionInfo{})
+		err = nodes.Create(&mgo.CollectionInfo{})
 		if err != nil {
 			return fmt.Errorf("error creating nodes collection in database %s: %v", db.conf.Database, err)
 		}
 
-		err = db.nodes.EnsureIndex(mgo.Index{
+		err = nodes.EnsureIndex(mgo.Index{
 			Key:        []string{"id"},
 			Unique:     true,
 			DropDups:   true,
diff --git a/database/mongodb/scheduler.go b/database/mongodb/scheduler.go
index 1ee482c9..d0fcc5be 100644
--- a/database/mongodb/scheduler.go
+++ b/database/mongodb/scheduler.go
@@ -3,19 +3,22 @@ package mongodb
 import (
 	"fmt"
 
+	"github.com/globalsign/mgo"
+	"github.com/globalsign/mgo/bson"
 	"github.com/ohsu-comp-bio/funnel/compute/scheduler"
 	"github.com/ohsu-comp-bio/funnel/tes"
 	"golang.org/x/net/context"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
-	"gopkg.in/mgo.v2"
-	"gopkg.in/mgo.v2/bson"
 )
 
 // ReadQueue returns a slice of queued Tasks. Up to "n" tasks are returned.
 func (db *MongoDB) ReadQueue(n int) []*tes.Task {
+	sess := db.sess.Copy()
+	defer sess.Close()
+
 	var tasks []*tes.Task
-	err := db.tasks.Find(bson.M{"state": tes.State_QUEUED}).Sort("creationtime").Select(basicView).Limit(n).All(&tasks)
+	err := db.tasks(sess).Find(bson.M{"state": tes.State_QUEUED}).Sort("creationtime").Select(basicView).Limit(n).All(&tasks)
 	if err != nil {
 		fmt.Println(err)
 		return nil
@@ -27,6 +30,10 @@ func (db *MongoDB) ReadQueue(n int) []*tes.Task {
 // and status updates, such as completed tasks. The server responds with updated
 // information for the node, such as canceled tasks.
 func (db *MongoDB) PutNode(ctx context.Context, node *scheduler.Node) (*scheduler.PutNodeResponse, error) {
+	sess := db.sess.Copy()
+	defer sess.Close()
+	nodes := db.nodes(sess)
+
 	q := bson.M{"id": node.Id}
 
 	if node.GetVersion() != 0 {
@@ -34,7 +41,7 @@ func (db *MongoDB) PutNode(ctx context.Context, node *scheduler.Node) (*schedule
 	}
 
 	var existing scheduler.Node
-	err := db.nodes.Find(bson.M{"id": node.Id}).One(&existing)
+	err := nodes.Find(bson.M{"id": node.Id}).One(&existing)
 	if err != nil && err != mgo.ErrNotFound {
 		return nil, err
 	}
@@ -46,15 +53,18 @@ func (db *MongoDB) PutNode(ctx context.Context, node *scheduler.Node) (*schedule
 
 	node.Version = node.GetVersion() + 1
 
-	_, err = db.nodes.Upsert(q, node)
+	_, err = nodes.Upsert(q, node)
 
 	return &scheduler.PutNodeResponse{}, err
 }
 
 // GetNode gets a node
 func (db *MongoDB) GetNode(ctx context.Context, req *scheduler.GetNodeRequest) (*scheduler.Node, error) {
+	sess := db.sess.Copy()
+	defer sess.Close()
+
 	var node scheduler.Node
-	err := db.nodes.Find(bson.M{"id": req.Id}).One(&node)
+	err := db.nodes(sess).Find(bson.M{"id": req.Id}).One(&node)
 	if err == mgo.ErrNotFound {
 		return nil, grpc.Errorf(codes.NotFound, fmt.Sprintf("%v: nodeID: %s", mgo.ErrNotFound.Error(), req.Id))
 	}
@@ -63,7 +73,10 @@ func (db *MongoDB) GetNode(ctx context.Context, req *scheduler.GetNodeRequest) (
 
 // DeleteNode deletes a node
 func (db *MongoDB) DeleteNode(ctx context.Context, req *scheduler.Node) (*scheduler.DeleteNodeResponse, error) {
-	err := db.nodes.Remove(bson.M{"id": req.Id})
+	sess := db.sess.Copy()
+	defer sess.Close()
+
+	err := db.nodes(sess).Remove(bson.M{"id": req.Id})
 	if err == mgo.ErrNotFound {
 		return nil, grpc.Errorf(codes.NotFound, fmt.Sprintf("%v: nodeID: %s", mgo.ErrNotFound.Error(), req.Id))
 	}
@@ -72,8 +85,11 @@ func (db *MongoDB) DeleteNode(ctx context.Context, req *scheduler.Node) (*schedu
 
 // ListNodes is an API endpoint that returns a list of nodes.
 func (db *MongoDB) ListNodes(ctx context.Context, req *scheduler.ListNodesRequest) (*scheduler.ListNodesResponse, error) {
+	sess := db.sess.Copy()
+	defer sess.Close()
+
 	var nodes []*scheduler.Node
-	err := db.nodes.Find(nil).All(&nodes)
+	err := db.nodes(sess).Find(nil).All(&nodes)
 	if err != nil {
 		return nil, err
 	}
diff --git a/database/mongodb/tes.go b/database/mongodb/tes.go
index e6a5a77c..30968fd8 100644
--- a/database/mongodb/tes.go
+++ b/database/mongodb/tes.go
@@ -3,10 +3,10 @@ package mongodb
 import (
 	"fmt"
 
+	"github.com/globalsign/mgo"
+	"github.com/globalsign/mgo/bson"
 	"github.com/ohsu-comp-bio/funnel/tes"
 	"golang.org/x/net/context"
-	"gopkg.in/mgo.v2"
-	"gopkg.in/mgo.v2/bson"
 )
 
 var basicView = bson.M{
@@ -19,10 +19,13 @@ var minimalView = bson.M{"id": 1, "state": 1}
 
 // GetTask gets a task, which describes a running task
 func (db *MongoDB) GetTask(ctx context.Context, req *tes.GetTaskRequest) (*tes.Task, error) {
+	sess := db.sess.Copy()
+	defer sess.Close()
+
 	var task tes.Task
 	var q *mgo.Query
 
-	q = db.tasks.Find(bson.M{"id": req.Id})
+	q = db.tasks(sess).Find(bson.M{"id": req.Id})
 	switch req.View {
 	case tes.TaskView_BASIC:
 		q = q.Select(basicView)
@@ -43,6 +46,9 @@ func (db *MongoDB) GetTask(ctx context.Context, req *tes.GetTaskRequest) (*tes.T
 
 // ListTasks returns a list of taskIDs
 func (db *MongoDB) ListTasks(ctx context.Context, req *tes.ListTasksRequest) (*tes.ListTasksResponse, error) {
+	sess := db.sess.Copy()
+	defer sess.Close()
+
 	pageSize := tes.GetPageSize(req.GetPageSize())
 
 	var query = bson.M{}
@@ -60,7 +66,7 @@ func (db *MongoDB) ListTasks(ctx context.Context, req *tes.ListTasksRequest) (*t
 		query[fmt.Sprintf("tags.%s", k)] = bson.M{"$eq": v}
 	}
 
-	q = db.tasks.Find(query).Sort("-creationtime").Limit(pageSize)
+	q = db.tasks(sess).Find(query).Sort("-creationtime").Limit(pageSize)
 
 	switch req.View {
 	case tes.TaskView_BASIC:
diff --git a/logger/grpc.go b/logger/grpc.go
index 426259c5..77f0481f 100644
--- a/logger/grpc.go
+++ b/logger/grpc.go
@@ -24,42 +24,42 @@ type grpclogger struct {
 }
 
 func (g *grpclogger) Info(args ...interface{}) {
-	g.log.Debug(fmt.Sprint(args))
+	g.log.Debug(fmt.Sprint(args...))
 }
 func (g *grpclogger) Infoln(args ...interface{}) {
-	g.log.Debug(fmt.Sprint(args))
+	g.log.Debug(fmt.Sprint(args...))
 }
 func (g *grpclogger) Infof(format string, args ...interface{}) {
-	g.log.Debug(fmt.Sprintf(format, args))
+	g.log.Debug(fmt.Sprintf(format, args...))
 }
 func (g *grpclogger) Warning(args ...interface{}) {
-	g.log.Debug(fmt.Sprint(args))
+	g.log.Debug(fmt.Sprint(args...))
 }
 func (g *grpclogger) Warningln(args ...interface{}) {
-	g.log.Debug(fmt.Sprint(args))
+	g.log.Debug(fmt.Sprint(args...))
 }
 func (g *grpclogger) Warningf(format string, args ...interface{}) {
-	g.log.Debug(fmt.Sprintf(format, args))
+	g.log.Debug(fmt.Sprintf(format, args...))
 }
 func (g *grpclogger) Error(args ...interface{}) {
-	g.log.Error(fmt.Sprint(args))
+	g.log.Error(fmt.Sprint(args...))
 }
 func (g *grpclogger) Errorln(args ...interface{}) {
-	g.log.Error(fmt.Sprint(args))
+	g.log.Error(fmt.Sprint(args...))
 }
 func (g *grpclogger) Errorf(format string, args ...interface{}) {
-	g.log.Error(fmt.Sprintf(format, args))
+	g.log.Error(fmt.Sprintf(format, args...))
 }
 func (g *grpclogger) Fatal(args ...interface{}) {
-	g.log.Error(fmt.Sprint(args))
+	g.log.Error(fmt.Sprint(args...))
 	os.Exit(1)
 }
 func (g *grpclogger) Fatalln(args ...interface{}) {
-	g.log.Error(fmt.Sprint(args))
+	g.log.Error(fmt.Sprint(args...))
 	os.Exit(1)
 }
 func (g *grpclogger) Fatalf(format string, args ...interface{}) {
-	g.log.Error(fmt.Sprintf(format, args))
+	g.log.Error(fmt.Sprintf(format, args...))
 	os.Exit(1)
 }
 func (g *grpclogger) V(l int) bool {
diff --git a/server/server.go b/server/server.go
index cb964a5e..251412b0 100644
--- a/server/server.go
+++ b/server/server.go
@@ -6,7 +6,7 @@ import (
 	"net/http"
 
 	"github.com/golang/gddo/httputil"
-	"github.com/grpc-ecosystem/go-grpc-middleware"
+	grpc_middleware "github.com/grpc-ecosystem/go-grpc-middleware"
 	"github.com/grpc-ecosystem/grpc-gateway/runtime"
 	"github.com/ohsu-comp-bio/funnel/compute/scheduler"
 	"github.com/ohsu-comp-bio/funnel/config"
diff --git a/server/tes.go b/server/tes.go
index 1b95291b..3d45558a 100644
--- a/server/tes.go
+++ b/server/tes.go
@@ -43,7 +43,12 @@ func (ts *TaskService) CreateTask(ctx context.Context, task *tes.Task) (*tes.Cre
 	}
 
 	// dispatch to compute backend
-	go ts.Compute.WriteEvent(ctx, events.NewTaskCreated(task))
+	go func() {
+		err := ts.Compute.WriteEvent(ctx, events.NewTaskCreated(task))
+		if err != nil {
+			ts.Log.Error("error submitting task to compute backend", "taskID", task.Id, "error", err)
+		}
+	}()
 
 	return &tes.CreateTaskResponse{Id: task.Id}, nil
 }
diff --git a/storage/http_test.go b/storage/http_test.go
index ad104e95..fba42461 100644
--- a/storage/http_test.go
+++ b/storage/http_test.go
@@ -17,7 +17,7 @@ func TestHTTP(t *testing.T) {
 	}
 
 	// test client timeout
-	err = store.UnsupportedOperations("https://fakeurl.com").Get
+	err = store.UnsupportedOperations("https://fakeurl1234.com").Get
 	if err == nil {
 		t.Error("Expected timeout error")
 	}
@@ -47,7 +47,7 @@ func TestHTTP(t *testing.T) {
 	}
 
 	// test Put not supported
-	_, err = store.Put(context.Background(), "https://fakeurl.com", "_test_download/test_https_download.html")
+	_, err = store.Put(context.Background(), "https://fakeurl1234.com", "_test_download/test_https_download.html")
 	if err == nil {
 		t.Error("Expected error for Put call")
 	}
diff --git a/util/rpc/rpc.go b/util/rpc/rpc.go
index 6498b396..67c84096 100644
--- a/util/rpc/rpc.go
+++ b/util/rpc/rpc.go
@@ -6,7 +6,7 @@ import (
 	"math/rand"
 	"time"
 
-	"github.com/grpc-ecosystem/go-grpc-middleware/retry"
+	grpc_retry "github.com/grpc-ecosystem/go-grpc-middleware/retry"
 	"github.com/ohsu-comp-bio/funnel/config"
 	"golang.org/x/net/context"
 	"google.golang.org/grpc"
diff --git a/webdash/http.go b/webdash/http.go
index ea7757ba..6e47e2fa 100644
--- a/webdash/http.go
+++ b/webdash/http.go
@@ -3,7 +3,7 @@ package webdash
 import (
 	"net/http"
 
-	"github.com/elazarl/go-bindata-assetfs"
+	assetfs "github.com/elazarl/go-bindata-assetfs"
 )
 
 var fs = &assetfs.AssetFS{