Merge branch 'disk-statistics' into 'master'

Add DiskStatistics grpc method to ServerService

Closes #2146

See merge request gitlab-org/gitaly!1620

9 files changed, 428 insertions, 23 deletions

diff --git a/changelogs/unreleased/disk-statistics.yml b/changelogs/unreleased/disk-statistics.yml
new file mode 100644
index 000000000..fc384258d
--- /dev/null
+++ b/changelogs/unreleased/disk-statistics.yml
@@ -0,0 +1,5 @@
+---
+title: Add DiskStatistics grpc method to ServerService
+merge_request: 1620
+author: maxmati
+type: added
diff --git a/internal/praefect/server_test.go b/internal/praefect/server_test.go
index 7f1b9d767..b75aa3c59 100644
--- a/internal/praefect/server_test.go
+++ b/internal/praefect/server_test.go
@@ -110,6 +110,38 @@ func TestGitalyServerInfo(t *testing.T) {
 	}
 }
 
+func TestGitalyDiskStatistics(t *testing.T) {
+	conf := config.Config{
+		Nodes: []*models.Node{
+			{
+				ID:             1,
+				Storage:        "praefect-internal-1",
+				DefaultPrimary: true,
+				Token:          "abc",
+			},
+			{
+				ID:      2,
+				Storage: "praefect-internal-2",
+				Token:   "xyz",
+			}},
+	}
+	cc, _, cleanup := runPraefectServerWithGitaly(t, conf)
+	defer cleanup()
+
+	client := gitalypb.NewServerServiceClient(cc)
+
+	ctx, cancel := testhelper.Context()
+	defer cancel()
+
+	metadata, err := client.DiskStatistics(ctx, &gitalypb.DiskStatisticsRequest{})
+	require.NoError(t, err)
+	require.Len(t, metadata.GetStorageStatuses(), len(conf.Nodes))
+
+	for _, storageStatus := range metadata.GetStorageStatuses() {
+		require.NotNil(t, storageStatus, "none of the storage statuses should be nil")
+	}
+}
+
 func TestHealthCheck(t *testing.T) {
 	cc, _, cleanup := runPraefectServerWithGitaly(t, testConfig(1))
 	defer cleanup()
diff --git a/internal/praefect/service/server/disk_stats.go b/internal/praefect/service/server/disk_stats.go
new file mode 100644
index 000000000..745817826
--- /dev/null
+++ b/internal/praefect/service/server/disk_stats.go
@@ -0,0 +1,51 @@
+package server
+
+import (
+	"context"
+	"fmt"
+
+	"gitlab.com/gitlab-org/gitaly/internal/helper"
+	"gitlab.com/gitlab-org/gitaly/proto/go/gitalypb"
+	"golang.org/x/sync/errgroup"
+)
+
+// DiskStatistics sends DiskStatisticsRequest to all of a praefect server's internal gitaly nodes and aggregates the
+// results into a response
+func (s *Server) DiskStatistics(ctx context.Context, _ *gitalypb.DiskStatisticsRequest) (*gitalypb.DiskStatisticsResponse, error) {
+	storageStatuses := make([][]*gitalypb.DiskStatisticsResponse_StorageStatus, len(s.conf.Nodes))
+
+	g, ctx := errgroup.WithContext(ctx)
+
+	for i, node := range s.conf.Nodes {
+		i := i // necessary since it will be used in a goroutine below
+		node := node
+		cc, err := s.clientCC.GetConnection(node.Storage)
+		if err != nil {
+			return nil, helper.ErrInternalf("error getting client connection for %s: %v", node.Storage, err)
+		}
+
+		g.Go(func() error {
+			client := gitalypb.NewServerServiceClient(cc)
+			resp, err := client.DiskStatistics(ctx, &gitalypb.DiskStatisticsRequest{})
+			if err != nil {
+				return fmt.Errorf("error when requesting disk statistics from internal storage %v", node.Storage)
+			}
+
+			storageStatuses[i] = resp.GetStorageStatuses()
+
+			return nil
+		})
+	}
+
+	if err := g.Wait(); err != nil {
+		return nil, helper.ErrInternal(err)
+	}
+
+	var response gitalypb.DiskStatisticsResponse
+
+	for _, storageStatus := range storageStatuses {
+		response.StorageStatuses = append(response.StorageStatuses, storageStatus...)
+	}
+
+	return &response, nil
+}
diff --git a/internal/service/server/disk_stats.go b/internal/service/server/disk_stats.go
new file mode 100644
index 000000000..f4f6b09a3
--- /dev/null
+++ b/internal/service/server/disk_stats.go
@@ -0,0 +1,46 @@
+package server
+
+import (
+	"context"
+
+	"github.com/grpc-ecosystem/go-grpc-middleware/logging/logrus/ctxlogrus"
+	"gitlab.com/gitlab-org/gitaly/internal/config"
+	"gitlab.com/gitlab-org/gitaly/proto/go/gitalypb"
+	"golang.org/x/sys/unix"
+)
+
+func (s *server) DiskStatistics(ctx context.Context, _ *gitalypb.DiskStatisticsRequest) (*gitalypb.DiskStatisticsResponse, error) {
+	var results []*gitalypb.DiskStatisticsResponse_StorageStatus
+	for _, shard := range config.Config.Storages {
+		shardInfo, err := getStorageStatus(shard)
+		if err != nil {
+			ctxlogrus.Extract(ctx).WithField("storage", shard).WithError(err).Error("to retrieve shard disk statistics")
+			results = append(results, &gitalypb.DiskStatisticsResponse_StorageStatus{StorageName: shard.Name})
+			continue
+		}
+
+		results = append(results, shardInfo)
+	}
+
+	return &gitalypb.DiskStatisticsResponse{
+		StorageStatuses: results,
+	}, nil
+}
+
+func getStorageStatus(shard config.Storage) (*gitalypb.DiskStatisticsResponse_StorageStatus, error) {
+	var stats unix.Statfs_t
+	err := unix.Statfs(shard.Path, &stats)
+	if err != nil {
+		return nil, err
+	}
+
+	// Redundant conversions to handle differences between unix families
+	available := int64(stats.Bavail) * int64(stats.Bsize)
+	used := (int64(stats.Blocks) - int64(stats.Bfree)) * int64(stats.Bsize)
+
+	return &gitalypb.DiskStatisticsResponse_StorageStatus{
+		StorageName: shard.Name,
+		Available:   available,
+		Used:        used,
+	}, nil
+}
diff --git a/internal/service/server/disk_stats_test.go b/internal/service/server/disk_stats_test.go
new file mode 100644
index 000000000..4ad8966c3
--- /dev/null
+++ b/internal/service/server/disk_stats_test.go
@@ -0,0 +1,65 @@
+package server
+
+import (
+	"math"
+	"testing"
+
+	"golang.org/x/sys/unix"
+
+	"github.com/stretchr/testify/require"
+	"gitlab.com/gitlab-org/gitaly/internal/config"
+	"gitlab.com/gitlab-org/gitaly/internal/testhelper"
+	"gitlab.com/gitlab-org/gitaly/proto/go/gitalypb"
+)
+
+func TestStorageDiskStatistics(t *testing.T) {
+	server, serverSocketPath := runServer(t)
+	defer server.Stop()
+
+	client, conn := newServerClient(t, serverSocketPath)
+	defer conn.Close()
+
+	ctx, cancel := testhelper.Context()
+	defer cancel()
+
+	// Setup storage paths
+	testStorages := []config.Storage{
+		{Name: "default", Path: testhelper.GitlabTestStoragePath()},
+		{Name: "broken", Path: "/does/not/exist"},
+	}
+	defer func(oldStorages []config.Storage) {
+		config.Config.Storages = oldStorages
+	}(config.Config.Storages)
+	config.Config.Storages = testStorages
+
+	c, err := client.DiskStatistics(ctx, &gitalypb.DiskStatisticsRequest{})
+	require.NoError(t, err)
+
+	require.Len(t, c.GetStorageStatuses(), len(testStorages))
+
+	//used and available space may change so we check if it roughly matches (+/- 1GB)
+	avail, used := getSpaceStats(t, testStorages[0].Path)
+	approxEqual(t, c.GetStorageStatuses()[0].Available, avail)
+	approxEqual(t, c.GetStorageStatuses()[0].Used, used)
+	require.Equal(t, testStorages[0].Name, c.GetStorageStatuses()[0].StorageName)
+
+	require.Equal(t, int64(0), c.GetStorageStatuses()[1].Available)
+	require.Equal(t, int64(0), c.GetStorageStatuses()[1].Used)
+	require.Equal(t, testStorages[1].Name, c.GetStorageStatuses()[1].StorageName)
+}
+
+func approxEqual(t *testing.T, a, b int64) {
+	const eps = 1024 * 1024 * 1024
+	require.Truef(t, math.Abs(float64(a-b)) < eps, "expected %d to be equal %d with epsilon %d", a, b, eps)
+}
+
+func getSpaceStats(t *testing.T, path string) (available int64, used int64) {
+	var stats unix.Statfs_t
+	err := unix.Statfs(path, &stats)
+	require.NoError(t, err)
+
+	// Redundant conversions to handle differences between unix families
+	available = int64(stats.Bavail) * int64(stats.Bsize)
+	used = (int64(stats.Blocks) - int64(stats.Bfree)) * int64(stats.Bsize)
+	return
+}
diff --git a/proto/go/gitalypb/server.pb.go b/proto/go/gitalypb/server.pb.go
index 879be71b0..f463b119e 100644
--- a/proto/go/gitalypb/server.pb.go
+++ b/proto/go/gitalypb/server.pb.go
@@ -181,38 +181,174 @@ func (m *ServerInfoResponse_StorageStatus) GetFilesystemId() string {
 	return ""
 }
 
+type DiskStatisticsRequest struct {
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *DiskStatisticsRequest) Reset()         { *m = DiskStatisticsRequest{} }
+func (m *DiskStatisticsRequest) String() string { return proto.CompactTextString(m) }
+func (*DiskStatisticsRequest) ProtoMessage()    {}
+func (*DiskStatisticsRequest) Descriptor() ([]byte, []int) {
+	return fileDescriptor_ad098daeda4239f7, []int{2}
+}
+
+func (m *DiskStatisticsRequest) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_DiskStatisticsRequest.Unmarshal(m, b)
+}
+func (m *DiskStatisticsRequest) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_DiskStatisticsRequest.Marshal(b, m, deterministic)
+}
+func (m *DiskStatisticsRequest) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_DiskStatisticsRequest.Merge(m, src)
+}
+func (m *DiskStatisticsRequest) XXX_Size() int {
+	return xxx_messageInfo_DiskStatisticsRequest.Size(m)
+}
+func (m *DiskStatisticsRequest) XXX_DiscardUnknown() {
+	xxx_messageInfo_DiskStatisticsRequest.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_DiskStatisticsRequest proto.InternalMessageInfo
+
+type DiskStatisticsResponse struct {
+	StorageStatuses      []*DiskStatisticsResponse_StorageStatus `protobuf:"bytes,1,rep,name=storage_statuses,json=storageStatuses,proto3" json:"storage_statuses,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}                                `json:"-"`
+	XXX_unrecognized     []byte                                  `json:"-"`
+	XXX_sizecache        int32                                   `json:"-"`
+}
+
+func (m *DiskStatisticsResponse) Reset()         { *m = DiskStatisticsResponse{} }
+func (m *DiskStatisticsResponse) String() string { return proto.CompactTextString(m) }
+func (*DiskStatisticsResponse) ProtoMessage()    {}
+func (*DiskStatisticsResponse) Descriptor() ([]byte, []int) {
+	return fileDescriptor_ad098daeda4239f7, []int{3}
+}
+
+func (m *DiskStatisticsResponse) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_DiskStatisticsResponse.Unmarshal(m, b)
+}
+func (m *DiskStatisticsResponse) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_DiskStatisticsResponse.Marshal(b, m, deterministic)
+}
+func (m *DiskStatisticsResponse) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_DiskStatisticsResponse.Merge(m, src)
+}
+func (m *DiskStatisticsResponse) XXX_Size() int {
+	return xxx_messageInfo_DiskStatisticsResponse.Size(m)
+}
+func (m *DiskStatisticsResponse) XXX_DiscardUnknown() {
+	xxx_messageInfo_DiskStatisticsResponse.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_DiskStatisticsResponse proto.InternalMessageInfo
+
+func (m *DiskStatisticsResponse) GetStorageStatuses() []*DiskStatisticsResponse_StorageStatus {
+	if m != nil {
+		return m.StorageStatuses
+	}
+	return nil
+}
+
+type DiskStatisticsResponse_StorageStatus struct {
+	// When both available and used fields are equal 0 that means that
+	// Gitaly was unable to determine storage stats.
+	StorageName          string   `protobuf:"bytes,1,opt,name=storage_name,json=storageName,proto3" json:"storage_name,omitempty"`
+	Available            int64    `protobuf:"varint,2,opt,name=available,proto3" json:"available,omitempty"`
+	Used                 int64    `protobuf:"varint,3,opt,name=used,proto3" json:"used,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *DiskStatisticsResponse_StorageStatus) Reset()         { *m = DiskStatisticsResponse_StorageStatus{} }
+func (m *DiskStatisticsResponse_StorageStatus) String() string { return proto.CompactTextString(m) }
+func (*DiskStatisticsResponse_StorageStatus) ProtoMessage()    {}
+func (*DiskStatisticsResponse_StorageStatus) Descriptor() ([]byte, []int) {
+	return fileDescriptor_ad098daeda4239f7, []int{3, 0}
+}
+
+func (m *DiskStatisticsResponse_StorageStatus) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_DiskStatisticsResponse_StorageStatus.Unmarshal(m, b)
+}
+func (m *DiskStatisticsResponse_StorageStatus) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_DiskStatisticsResponse_StorageStatus.Marshal(b, m, deterministic)
+}
+func (m *DiskStatisticsResponse_StorageStatus) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_DiskStatisticsResponse_StorageStatus.Merge(m, src)
+}
+func (m *DiskStatisticsResponse_StorageStatus) XXX_Size() int {
+	return xxx_messageInfo_DiskStatisticsResponse_StorageStatus.Size(m)
+}
+func (m *DiskStatisticsResponse_StorageStatus) XXX_DiscardUnknown() {
+	xxx_messageInfo_DiskStatisticsResponse_StorageStatus.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_DiskStatisticsResponse_StorageStatus proto.InternalMessageInfo
+
+func (m *DiskStatisticsResponse_StorageStatus) GetStorageName() string {
+	if m != nil {
+		return m.StorageName
+	}
+	return ""
+}
+
+func (m *DiskStatisticsResponse_StorageStatus) GetAvailable() int64 {
+	if m != nil {
+		return m.Available
+	}
+	return 0
+}
+
+func (m *DiskStatisticsResponse_StorageStatus) GetUsed() int64 {
+	if m != nil {
+		return m.Used
+	}
+	return 0
+}
+
 func init() {
 	proto.RegisterType((*ServerInfoRequest)(nil), "gitaly.ServerInfoRequest")
 	proto.RegisterType((*ServerInfoResponse)(nil), "gitaly.ServerInfoResponse")
 	proto.RegisterType((*ServerInfoResponse_StorageStatus)(nil), "gitaly.ServerInfoResponse.StorageStatus")
+	proto.RegisterType((*DiskStatisticsRequest)(nil), "gitaly.DiskStatisticsRequest")
+	proto.RegisterType((*DiskStatisticsResponse)(nil), "gitaly.DiskStatisticsResponse")
+	proto.RegisterType((*DiskStatisticsResponse_StorageStatus)(nil), "gitaly.DiskStatisticsResponse.StorageStatus")
 }
 
 func init() { proto.RegisterFile("server.proto", fileDescriptor_ad098daeda4239f7) }
 
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+	0xec, 0x9a, 0x49, 0x4f, 0x3a, 0xf1, 0x2c, 0x9e, 0x1f, 0xc1, 0xed, 0x97, 0x82, 0x3e, 0xd5, 0x83,
+	0x0a, 0xd2, 0x62, 0x4d, 0x2d, 0xf9, 0x1f, 0x0e, 0xdc, 0xf9, 0x33, 0xd3, 0xd0, 0x7f, 0xb7, 0x87,
+	0x9a, 0x63, 0xa8, 0x3d, 0x69, 0xa9, 0xed, 0xaf, 0xfc, 0x1f, 0xb9, 0xf8, 0x0a, 0xe0, 0x8e, 0x61,
+	0xc4, 0xb7, 0x5c, 0x64, 0x3b, 0x72, 0x6e, 0xd0, 0x09, 0x8c, 0x41, 0x7f, 0x43, 0x18, 0x1b, 0x6a,
+	0x6e, 0x60, 0xce, 0xa7, 0xdf, 0xeb, 0xfd, 0x98, 0xad, 0xd6, 0x4f, 0xb1, 0x46, 0xf6, 0x0a, 0xa0,
+	0x5b, 0x33, 0xbb, 0xbb, 0x6f, 0xf5, 0x06, 0x8a, 0xe7, 0x5d, 0xfe, 0x55, 0xcc, 0x87, 0xbf, 0xbe,
+	0x2e, 0xfa, 0xc3, 0xde, 0xa1, 0xc3, 0xde, 0xc3, 0xc1, 0xc5, 0xf7, 0x67, 0xf7, 0x2e, 0xe3, 0x62,
+	0xdb, 0xde, 0xff, 0x37, 0xb6, 0xae, 0xf5, 0x8b, 0x67, 0x1f, 0x6a, 0x6b, 0xc6, 0x23, 0x7f, 0x2d,
+	0xf3, 0xa5, 0x3d, 0x3e, 0x95, 0x2a, 0x5d, 0xda, 0x06, 0x4b, 0xf3, 0x2b, 0x2d, 0x53, 0xd9, 0xc4,
+	0x65, 0x14, 0x0d, 0x8c, 0xf4, 0xfc, 0x77, 0x00, 0x00, 0x00, 0xff, 0xff, 0x2d, 0xba, 0x46, 0xb9,
+	0x83, 0x03, 0x00, 0x00,
 }
 
 // Reference imports to suppress errors if they are not otherwise used.
@@ -228,6 +364,7 @@ const _ = grpc.SupportPackageIsVersion4
 // For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
 type ServerServiceClient interface {
 	ServerInfo(ctx context.Context, in *ServerInfoRequest, opts ...grpc.CallOption) (*ServerInfoResponse, error)
+	DiskStatistics(ctx context.Context, in *DiskStatisticsRequest, opts ...grpc.CallOption) (*DiskStatisticsResponse, error)
 }
 
 type serverServiceClient struct {
@@ -247,9 +384,19 @@ func (c *serverServiceClient) ServerInfo(ctx context.Context, in *ServerInfoRequ
 	return out, nil
 }
 
+func (c *serverServiceClient) DiskStatistics(ctx context.Context, in *DiskStatisticsRequest, opts ...grpc.CallOption) (*DiskStatisticsResponse, error) {
+	out := new(DiskStatisticsResponse)
+	err := c.cc.Invoke(ctx, "/gitaly.ServerService/DiskStatistics", in, out, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 // ServerServiceServer is the server API for ServerService service.
 type ServerServiceServer interface {
 	ServerInfo(context.Context, *ServerInfoRequest) (*ServerInfoResponse, error)
+	DiskStatistics(context.Context, *DiskStatisticsRequest) (*DiskStatisticsResponse, error)
 }
 
 // UnimplementedServerServiceServer can be embedded to have forward compatible implementations.
@@ -259,6 +406,9 @@ type UnimplementedServerServiceServer struct {
 func (*UnimplementedServerServiceServer) ServerInfo(ctx context.Context, req *ServerInfoRequest) (*ServerInfoResponse, error) {
 	return nil, status.Errorf(codes.Unimplemented, "method ServerInfo not implemented")
 }
+func (*UnimplementedServerServiceServer) DiskStatistics(ctx context.Context, req *DiskStatisticsRequest) (*DiskStatisticsResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method DiskStatistics not implemented")
+}
 
 func RegisterServerServiceServer(s *grpc.Server, srv ServerServiceServer) {
 	s.RegisterService(&_ServerService_serviceDesc, srv)
@@ -282,6 +432,24 @@ func _ServerService_ServerInfo_Handler(srv interface{}, ctx context.Context, dec
 	return interceptor(ctx, in, info, handler)
 }
 
+func _ServerService_DiskStatistics_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(DiskStatisticsRequest)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(ServerServiceServer).DiskStatistics(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: "/gitaly.ServerService/DiskStatistics",
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(ServerServiceServer).DiskStatistics(ctx, req.(*DiskStatisticsRequest))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
 var _ServerService_serviceDesc = grpc.ServiceDesc{
 	ServiceName: "gitaly.ServerService",
 	HandlerType: (*ServerServiceServer)(nil),
@@ -290,6 +458,10 @@ var _ServerService_serviceDesc = grpc.ServiceDesc{
 			MethodName: "ServerInfo",
 			Handler:    _ServerService_ServerInfo_Handler,
 		},
+		{
+			MethodName: "DiskStatistics",
+			Handler:    _ServerService_DiskStatistics_Handler,
+		},
 	},
 	Streams:  []grpc.StreamDesc{},
 	Metadata: "server.proto",
diff --git a/proto/server.proto b/proto/server.proto
index 6774eeae4..68e39f2fe 100644
--- a/proto/server.proto
+++ b/proto/server.proto
@@ -13,6 +13,12 @@ service ServerService {
       scope_level: SERVER
     };
   }
+  rpc DiskStatistics(DiskStatisticsRequest) returns (DiskStatisticsResponse) {
+    option (op_type) = {
+      op: ACCESSOR
+      scope_level: SERVER
+    };
+  }
 }
 
 message ServerInfoRequest {}
@@ -30,3 +36,17 @@ message ServerInfoResponse {
   string git_version = 2;
   repeated StorageStatus storage_statuses = 3;
 }
+
+message DiskStatisticsRequest {}
+
+message DiskStatisticsResponse {
+  message StorageStatus {
+// When both available and used fields are equal 0 that means that
+// Gitaly was unable to determine storage stats.
+    string storage_name = 1;
+    int64 available = 2;
+    int64 used = 3;
+  }
+
+  repeated StorageStatus storage_statuses = 1;
+}
diff --git a/ruby/proto/gitaly/server_pb.rb b/ruby/proto/gitaly/server_pb.rb
index e977d209f..c156f6e88 100644
--- a/ruby/proto/gitaly/server_pb.rb
+++ b/ruby/proto/gitaly/server_pb.rb
@@ -19,10 +19,23 @@ Google::Protobuf::DescriptorPool.generated_pool.build do
     optional :fs_type, :string, 4
     optional :filesystem_id, :string, 5
   end
+  add_message "gitaly.DiskStatisticsRequest" do
+  end
+  add_message "gitaly.DiskStatisticsResponse" do
+    repeated :storage_statuses, :message, 1, "gitaly.DiskStatisticsResponse.StorageStatus"
+  end
+  add_message "gitaly.DiskStatisticsResponse.StorageStatus" do
+    optional :storage_name, :string, 1
+    optional :available, :int64, 2
+    optional :used, :int64, 3
+  end
 end
 
 module Gitaly
   ServerInfoRequest = Google::Protobuf::DescriptorPool.generated_pool.lookup("gitaly.ServerInfoRequest").msgclass
   ServerInfoResponse = Google::Protobuf::DescriptorPool.generated_pool.lookup("gitaly.ServerInfoResponse").msgclass
   ServerInfoResponse::StorageStatus = Google::Protobuf::DescriptorPool.generated_pool.lookup("gitaly.ServerInfoResponse.StorageStatus").msgclass
+  DiskStatisticsRequest = Google::Protobuf::DescriptorPool.generated_pool.lookup("gitaly.DiskStatisticsRequest").msgclass
+  DiskStatisticsResponse = Google::Protobuf::DescriptorPool.generated_pool.lookup("gitaly.DiskStatisticsResponse").msgclass
+  DiskStatisticsResponse::StorageStatus = Google::Protobuf::DescriptorPool.generated_pool.lookup("gitaly.DiskStatisticsResponse.StorageStatus").msgclass
 end
diff --git a/ruby/proto/gitaly/server_services_pb.rb b/ruby/proto/gitaly/server_services_pb.rb
index 67c68f99e..df3e29b1e 100644
--- a/ruby/proto/gitaly/server_services_pb.rb
+++ b/ruby/proto/gitaly/server_services_pb.rb
@@ -15,6 +15,7 @@ module Gitaly
       self.service_name = 'gitaly.ServerService'
 
       rpc :ServerInfo, ServerInfoRequest, ServerInfoResponse
+      rpc :DiskStatistics, DiskStatisticsRequest, DiskStatisticsResponse
     end
 
     Stub = Service.rpc_stub_class