services/keep-balance/balance_run_test.go

   1 // Copyright (C) The Arvados Authors. All rights reserved.
   2 //
   3 // SPDX-License-Identifier: AGPL-3.0
   4
   5 package main
   6
   7 import (
   8         "bytes"
   9         "encoding/json"
  10         "fmt"
  11         "io"
  12         "io/ioutil"
  13         "net/http"
  14         "net/http/httptest"
  15         "os"
  16         "strings"
  17         "sync"
  18         "time"
  19
  20         "git.arvados.org/arvados.git/lib/config"
  21         "git.arvados.org/arvados.git/sdk/go/arvados"
  22         "git.arvados.org/arvados.git/sdk/go/arvadostest"
  23         "git.arvados.org/arvados.git/sdk/go/ctxlog"
  24         "github.com/jmoiron/sqlx"
  25         "github.com/prometheus/client_golang/prometheus"
  26         "github.com/prometheus/common/expfmt"
  27         check "gopkg.in/check.v1"
  28 )
  29
  30 var _ = check.Suite(&runSuite{})
  31
  32 type reqTracker struct {
  33         reqs []http.Request
  34         sync.Mutex
  35 }
  36
  37 func (rt *reqTracker) Count() int {
  38         rt.Lock()
  39         defer rt.Unlock()
  40         return len(rt.reqs)
  41 }
  42
  43 func (rt *reqTracker) Add(req *http.Request) int {
  44         rt.Lock()
  45         defer rt.Unlock()
  46         rt.reqs = append(rt.reqs, *req)
  47         return len(rt.reqs)
  48 }
  49
  50 var stubServices = []arvados.KeepService{
  51         {
  52                 UUID:           "zzzzz-bi6l4-000000000000000",
  53                 ServiceHost:    "keep0.zzzzz.arvadosapi.com",
  54                 ServicePort:    25107,
  55                 ServiceSSLFlag: false,
  56                 ServiceType:    "disk",
  57         },
  58         {
  59                 UUID:           "zzzzz-bi6l4-000000000000001",
  60                 ServiceHost:    "keep1.zzzzz.arvadosapi.com",
  61                 ServicePort:    25107,
  62                 ServiceSSLFlag: false,
  63                 ServiceType:    "disk",
  64         },
  65         {
  66                 UUID:           "zzzzz-bi6l4-000000000000002",
  67                 ServiceHost:    "keep2.zzzzz.arvadosapi.com",
  68                 ServicePort:    25107,
  69                 ServiceSSLFlag: false,
  70                 ServiceType:    "disk",
  71         },
  72         {
  73                 UUID:           "zzzzz-bi6l4-000000000000003",
  74                 ServiceHost:    "keep3.zzzzz.arvadosapi.com",
  75                 ServicePort:    25107,
  76                 ServiceSSLFlag: false,
  77                 ServiceType:    "disk",
  78         },
  79         {
  80                 UUID:           "zzzzz-bi6l4-h0a0xwut9qa6g3a",
  81                 ServiceHost:    "keep.zzzzz.arvadosapi.com",
  82                 ServicePort:    25333,
  83                 ServiceSSLFlag: true,
  84                 ServiceType:    "proxy",
  85         },
  86 }
  87
  88 var stubMounts = map[string][]arvados.KeepMount{
  89         "keep0.zzzzz.arvadosapi.com:25107": {{
  90                 UUID:           "zzzzz-ivpuk-000000000000000",
  91                 DeviceID:       "keep0-vol0",
  92                 StorageClasses: map[string]bool{"default": true},
  93         }},
  94         "keep1.zzzzz.arvadosapi.com:25107": {{
  95                 UUID:           "zzzzz-ivpuk-100000000000000",
  96                 DeviceID:       "keep1-vol0",
  97                 StorageClasses: map[string]bool{"default": true},
  98         }},
  99         "keep2.zzzzz.arvadosapi.com:25107": {{
 100                 UUID:           "zzzzz-ivpuk-200000000000000",
 101                 DeviceID:       "keep2-vol0",
 102                 StorageClasses: map[string]bool{"default": true},
 103         }},
 104         "keep3.zzzzz.arvadosapi.com:25107": {{
 105                 UUID:           "zzzzz-ivpuk-300000000000000",
 106                 DeviceID:       "keep3-vol0",
 107                 StorageClasses: map[string]bool{"default": true},
 108         }},
 109 }
 110
 111 // stubServer is an HTTP transport that intercepts and processes all
 112 // requests using its own handlers.
 113 type stubServer struct {
 114         mux      *http.ServeMux
 115         srv      *httptest.Server
 116         mutex    sync.Mutex
 117         Requests reqTracker
 118         logf     func(string, ...interface{})
 119 }
 120
 121 // Start initializes the stub server and returns an *http.Client that
 122 // uses the stub server to handle all requests.
 123 //
 124 // A stubServer that has been started should eventually be shut down
 125 // with Close().
 126 func (s *stubServer) Start() *http.Client {
 127         // Set up a config.Client that forwards all requests to s.mux
 128         // via s.srv. Test cases will attach handlers to s.mux to get
 129         // the desired responses.
 130         s.mux = http.NewServeMux()
 131         s.srv = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 132                 s.mutex.Lock()
 133                 s.Requests.Add(r)
 134                 s.mutex.Unlock()
 135                 w.Header().Set("Content-Type", "application/json")
 136                 s.mux.ServeHTTP(w, r)
 137         }))
 138         return &http.Client{Transport: s}
 139 }
 140
 141 func (s *stubServer) RoundTrip(req *http.Request) (*http.Response, error) {
 142         w := httptest.NewRecorder()
 143         s.mux.ServeHTTP(w, req)
 144         return &http.Response{
 145                 StatusCode: w.Code,
 146                 Status:     fmt.Sprintf("%d %s", w.Code, http.StatusText(w.Code)),
 147                 Header:     w.HeaderMap,
 148                 Body:       ioutil.NopCloser(w.Body)}, nil
 149 }
 150
 151 // Close releases resources used by the server.
 152 func (s *stubServer) Close() {
 153         s.srv.Close()
 154 }
 155
 156 func (s *stubServer) serveStatic(path, data string) *reqTracker {
 157         rt := &reqTracker{}
 158         s.mux.HandleFunc(path, func(w http.ResponseWriter, r *http.Request) {
 159                 rt.Add(r)
 160                 if r.Body != nil {
 161                         ioutil.ReadAll(r.Body)
 162                         r.Body.Close()
 163                 }
 164                 io.WriteString(w, data)
 165         })
 166         return rt
 167 }
 168
 169 func (s *stubServer) serveCurrentUserAdmin() *reqTracker {
 170         return s.serveStatic("/arvados/v1/users/current",
 171                 `{"uuid":"zzzzz-tpzed-000000000000000","is_admin":true,"is_active":true}`)
 172 }
 173
 174 func (s *stubServer) serveCurrentUserNotAdmin() *reqTracker {
 175         return s.serveStatic("/arvados/v1/users/current",
 176                 `{"uuid":"zzzzz-tpzed-000000000000000","is_admin":false,"is_active":true}`)
 177 }
 178
 179 func (s *stubServer) serveDiscoveryDoc() *reqTracker {
 180         return s.serveStatic("/discovery/v1/apis/arvados/v1/rest",
 181                 `{"defaultCollectionReplication":2}`)
 182 }
 183
 184 func (s *stubServer) serveZeroCollections() *reqTracker {
 185         return s.serveStatic("/arvados/v1/collections",
 186                 `{"items":[],"items_available":0}`)
 187 }
 188
 189 func (s *stubServer) serveFooBarFileCollections() *reqTracker {
 190         rt := &reqTracker{}
 191         s.mux.HandleFunc("/arvados/v1/collections", func(w http.ResponseWriter, r *http.Request) {
 192                 r.ParseForm()
 193                 rt.Add(r)
 194                 if strings.Contains(r.Form.Get("filters"), `modified_at`) {
 195                         io.WriteString(w, `{"items_available":0,"items":[]}`)
 196                 } else {
 197                         io.WriteString(w, `{"items_available":3,"items":[
 198                                 {"uuid":"zzzzz-4zz18-aaaaaaaaaaaaaaa","portable_data_hash":"fa7aeb5140e2848d39b416daeef4ffc5+45","manifest_text":". 37b51d194a7513e45b56f6524f2d51f2+3 0:3:bar\n","modified_at":"2014-02-03T17:22:54Z"},
 199                                 {"uuid":"zzzzz-4zz18-ehbhgtheo8909or","portable_data_hash":"fa7aeb5140e2848d39b416daeef4ffc5+45","manifest_text":". 37b51d194a7513e45b56f6524f2d51f2+3 0:3:bar\n","modified_at":"2014-02-03T17:22:54Z"},
 200                                 {"uuid":"zzzzz-4zz18-znfnqtbbv4spc3w","portable_data_hash":"1f4b0bc7583c2a7f9102c395f4ffc5e3+45","manifest_text":". acbd18db4cc2f85cedef654fccc4a4d8+3 0:3:foo\n","modified_at":"2014-02-03T17:22:54Z"}]}`)
 201                 }
 202         })
 203         return rt
 204 }
 205
 206 func (s *stubServer) serveCollectionsButSkipOne() *reqTracker {
 207         rt := &reqTracker{}
 208         s.mux.HandleFunc("/arvados/v1/collections", func(w http.ResponseWriter, r *http.Request) {
 209                 r.ParseForm()
 210                 rt.Add(r)
 211                 if strings.Contains(r.Form.Get("filters"), `"modified_at","\u003c="`) {
 212                         io.WriteString(w, `{"items_available":3,"items":[]}`)
 213                 } else if strings.Contains(r.Form.Get("filters"), `"modified_at","\u003e`) {
 214                         io.WriteString(w, `{"items_available":0,"items":[]}`)
 215                 } else if strings.Contains(r.Form.Get("filters"), `"modified_at","="`) && strings.Contains(r.Form.Get("filters"), `"uuid","\u003e"`) {
 216                         io.WriteString(w, `{"items_available":0,"items":[]}`)
 217                 } else if strings.Contains(r.Form.Get("filters"), `"modified_at","=",null`) {
 218                         io.WriteString(w, `{"items_available":0,"items":[]}`)
 219                 } else {
 220                         io.WriteString(w, `{"items_available":2,"items":[
 221                                 {"uuid":"zzzzz-4zz18-ehbhgtheo8909or","portable_data_hash":"fa7aeb5140e2848d39b416daeef4ffc5+45","manifest_text":". 37b51d194a7513e45b56f6524f2d51f2+3 0:3:bar\n","modified_at":"2014-02-03T17:22:54Z"},
 222                                 {"uuid":"zzzzz-4zz18-znfnqtbbv4spc3w","portable_data_hash":"1f4b0bc7583c2a7f9102c395f4ffc5e3+45","manifest_text":". acbd18db4cc2f85cedef654fccc4a4d8+3 0:3:foo\n","modified_at":"2014-02-03T17:22:54Z"}]}`)
 223                 }
 224         })
 225         return rt
 226 }
 227
 228 func (s *stubServer) serveZeroKeepServices() *reqTracker {
 229         return s.serveJSON("/arvados/v1/keep_services", arvados.KeepServiceList{})
 230 }
 231
 232 func (s *stubServer) serveKeepServices(svcs []arvados.KeepService) *reqTracker {
 233         return s.serveJSON("/arvados/v1/keep_services", arvados.KeepServiceList{
 234                 ItemsAvailable: len(svcs),
 235                 Items:          svcs,
 236         })
 237 }
 238
 239 func (s *stubServer) serveJSON(path string, resp interface{}) *reqTracker {
 240         rt := &reqTracker{}
 241         s.mux.HandleFunc(path, func(w http.ResponseWriter, r *http.Request) {
 242                 rt.Add(r)
 243                 json.NewEncoder(w).Encode(resp)
 244         })
 245         return rt
 246 }
 247
 248 func (s *stubServer) serveKeepstoreMounts() *reqTracker {
 249         rt := &reqTracker{}
 250         s.mux.HandleFunc("/mounts", func(w http.ResponseWriter, r *http.Request) {
 251                 rt.Add(r)
 252                 json.NewEncoder(w).Encode(stubMounts[r.Host])
 253         })
 254         return rt
 255 }
 256
 257 func (s *stubServer) serveKeepstoreIndexFoo4Bar1() *reqTracker {
 258         rt := &reqTracker{}
 259         s.mux.HandleFunc("/index/", func(w http.ResponseWriter, r *http.Request) {
 260                 count := rt.Add(r)
 261                 if r.Host == "keep0.zzzzz.arvadosapi.com:25107" {
 262                         io.WriteString(w, "37b51d194a7513e45b56f6524f2d51f2+3 12345678\n")
 263                 }
 264                 fmt.Fprintf(w, "acbd18db4cc2f85cedef654fccc4a4d8+3 %d\n\n", 12345678+count)
 265         })
 266         for _, mounts := range stubMounts {
 267                 for i, mnt := range mounts {
 268                         i := i
 269                         s.mux.HandleFunc(fmt.Sprintf("/mounts/%s/blocks", mnt.UUID), func(w http.ResponseWriter, r *http.Request) {
 270                                 count := rt.Add(r)
 271                                 if i == 0 && r.Host == "keep0.zzzzz.arvadosapi.com:25107" {
 272                                         io.WriteString(w, "37b51d194a7513e45b56f6524f2d51f2+3 12345678\n")
 273                                 }
 274                                 if i == 0 {
 275                                         fmt.Fprintf(w, "acbd18db4cc2f85cedef654fccc4a4d8+3 %d\n", 12345678+count)
 276                                 }
 277                                 fmt.Fprintf(w, "\n")
 278                         })
 279                 }
 280         }
 281         return rt
 282 }
 283
 284 func (s *stubServer) serveKeepstoreIndexFoo1() *reqTracker {
 285         rt := &reqTracker{}
 286         s.mux.HandleFunc("/index/", func(w http.ResponseWriter, r *http.Request) {
 287                 rt.Add(r)
 288                 io.WriteString(w, "acbd18db4cc2f85cedef654fccc4a4d8+3 12345678\n\n")
 289         })
 290         for _, mounts := range stubMounts {
 291                 for i, mnt := range mounts {
 292                         i := i
 293                         s.mux.HandleFunc(fmt.Sprintf("/mounts/%s/blocks", mnt.UUID), func(w http.ResponseWriter, r *http.Request) {
 294                                 rt.Add(r)
 295                                 if i == 0 {
 296                                         io.WriteString(w, "acbd18db4cc2f85cedef654fccc4a4d8+3 12345678\n\n")
 297                                 } else {
 298                                         io.WriteString(w, "\n")
 299                                 }
 300                         })
 301                 }
 302         }
 303         return rt
 304 }
 305
 306 func (s *stubServer) serveKeepstoreTrash() *reqTracker {
 307         return s.serveStatic("/trash", `{}`)
 308 }
 309
 310 func (s *stubServer) serveKeepstorePull() *reqTracker {
 311         return s.serveStatic("/pull", `{}`)
 312 }
 313
 314 type runSuite struct {
 315         stub   stubServer
 316         config *arvados.Cluster
 317         db     *sqlx.DB
 318         client *arvados.Client
 319 }
 320
 321 func (s *runSuite) newServer(options *RunOptions) *Server {
 322         srv := &Server{
 323                 Cluster:    s.config,
 324                 ArvClient:  s.client,
 325                 RunOptions: *options,
 326                 Metrics:    newMetrics(prometheus.NewRegistry()),
 327                 Logger:     options.Logger,
 328                 Dumper:     options.Dumper,
 329                 DB:         s.db,
 330         }
 331         return srv
 332 }
 333
 334 func (s *runSuite) SetUpTest(c *check.C) {
 335         cfg, err := config.NewLoader(nil, ctxlog.TestLogger(c)).Load()
 336         c.Assert(err, check.Equals, nil)
 337         s.config, err = cfg.GetCluster("")
 338         c.Assert(err, check.Equals, nil)
 339         s.db, err = sqlx.Open("postgres", s.config.PostgreSQL.Connection.String())
 340         c.Assert(err, check.IsNil)
 341
 342         s.config.Collections.BalancePeriod = arvados.Duration(time.Second)
 343         arvadostest.SetServiceURL(&s.config.Services.Keepbalance, "http://localhost:/")
 344
 345         s.client = &arvados.Client{
 346                 AuthToken: "xyzzy",
 347                 APIHost:   "zzzzz.arvadosapi.com",
 348                 Client:    s.stub.Start()}
 349
 350         s.stub.serveDiscoveryDoc()
 351         s.stub.logf = c.Logf
 352 }
 353
 354 func (s *runSuite) TearDownTest(c *check.C) {
 355         s.stub.Close()
 356 }
 357
 358 func (s *runSuite) TestRefuseZeroCollections(c *check.C) {
 359         defer arvados.NewClientFromEnv().RequestAndDecode(nil, "POST", "database/reset", nil, nil)
 360         _, err := s.db.Exec(`delete from collections`)
 361         c.Assert(err, check.IsNil)
 362         opts := RunOptions{
 363                 CommitPulls: true,
 364                 CommitTrash: true,
 365                 Logger:      ctxlog.TestLogger(c),
 366         }
 367         s.stub.serveCurrentUserAdmin()
 368         s.stub.serveZeroCollections()
 369         s.stub.serveKeepServices(stubServices)
 370         s.stub.serveKeepstoreMounts()
 371         s.stub.serveKeepstoreIndexFoo4Bar1()
 372         trashReqs := s.stub.serveKeepstoreTrash()
 373         pullReqs := s.stub.serveKeepstorePull()
 374         srv := s.newServer(&opts)
 375         _, err = srv.runOnce()
 376         c.Check(err, check.ErrorMatches, "received zero collections")
 377         c.Check(trashReqs.Count(), check.Equals, 4)
 378         c.Check(pullReqs.Count(), check.Equals, 0)
 379 }
 380
 381 func (s *runSuite) TestRefuseNonAdmin(c *check.C) {
 382         opts := RunOptions{
 383                 CommitPulls: true,
 384                 CommitTrash: true,
 385                 Logger:      ctxlog.TestLogger(c),
 386         }
 387         s.stub.serveCurrentUserNotAdmin()
 388         s.stub.serveZeroCollections()
 389         s.stub.serveKeepServices(stubServices)
 390         s.stub.serveKeepstoreMounts()
 391         trashReqs := s.stub.serveKeepstoreTrash()
 392         pullReqs := s.stub.serveKeepstorePull()
 393         srv := s.newServer(&opts)
 394         _, err := srv.runOnce()
 395         c.Check(err, check.ErrorMatches, "current user .* is not .* admin user")
 396         c.Check(trashReqs.Count(), check.Equals, 0)
 397         c.Check(pullReqs.Count(), check.Equals, 0)
 398 }
 399
 400 func (s *runSuite) TestWriteLostBlocks(c *check.C) {
 401         lostf, err := ioutil.TempFile("", "keep-balance-lost-blocks-test-")
 402         c.Assert(err, check.IsNil)
 403         s.config.Collections.BlobMissingReport = lostf.Name()
 404         defer os.Remove(lostf.Name())
 405         opts := RunOptions{
 406                 CommitPulls: true,
 407                 CommitTrash: true,
 408                 Logger:      ctxlog.TestLogger(c),
 409         }
 410         s.stub.serveCurrentUserAdmin()
 411         s.stub.serveFooBarFileCollections()
 412         s.stub.serveKeepServices(stubServices)
 413         s.stub.serveKeepstoreMounts()
 414         s.stub.serveKeepstoreIndexFoo1()
 415         s.stub.serveKeepstoreTrash()
 416         s.stub.serveKeepstorePull()
 417         srv := s.newServer(&opts)
 418         c.Assert(err, check.IsNil)
 419         _, err = srv.runOnce()
 420         c.Check(err, check.IsNil)
 421         lost, err := ioutil.ReadFile(lostf.Name())
 422         c.Assert(err, check.IsNil)
 423         c.Check(string(lost), check.Matches, `(?ms).*37b51d194a7513e45b56f6524f2d51f2.* fa7aeb5140e2848d39b416daeef4ffc5\+45.*`)
 424 }
 425
 426 func (s *runSuite) TestDryRun(c *check.C) {
 427         opts := RunOptions{
 428                 CommitPulls: false,
 429                 CommitTrash: false,
 430                 Logger:      ctxlog.TestLogger(c),
 431         }
 432         s.stub.serveCurrentUserAdmin()
 433         collReqs := s.stub.serveFooBarFileCollections()
 434         s.stub.serveKeepServices(stubServices)
 435         s.stub.serveKeepstoreMounts()
 436         s.stub.serveKeepstoreIndexFoo4Bar1()
 437         trashReqs := s.stub.serveKeepstoreTrash()
 438         pullReqs := s.stub.serveKeepstorePull()
 439         srv := s.newServer(&opts)
 440         bal, err := srv.runOnce()
 441         c.Check(err, check.IsNil)
 442         for _, req := range collReqs.reqs {
 443                 c.Check(req.Form.Get("include_trash"), check.Equals, "true")
 444                 c.Check(req.Form.Get("include_old_versions"), check.Equals, "true")
 445         }
 446         c.Check(trashReqs.Count(), check.Equals, 0)
 447         c.Check(pullReqs.Count(), check.Equals, 0)
 448         c.Check(bal.stats.pulls, check.Not(check.Equals), 0)
 449         c.Check(bal.stats.underrep.replicas, check.Not(check.Equals), 0)
 450         c.Check(bal.stats.overrep.replicas, check.Not(check.Equals), 0)
 451 }
 452
 453 func (s *runSuite) TestCommit(c *check.C) {
 454         s.config.Collections.BlobMissingReport = c.MkDir() + "/keep-balance-lost-blocks-test-"
 455         s.config.ManagementToken = "xyzzy"
 456         opts := RunOptions{
 457                 CommitPulls: true,
 458                 CommitTrash: true,
 459                 Logger:      ctxlog.TestLogger(c),
 460                 Dumper:      ctxlog.TestLogger(c),
 461         }
 462         s.stub.serveCurrentUserAdmin()
 463         s.stub.serveFooBarFileCollections()
 464         s.stub.serveKeepServices(stubServices)
 465         s.stub.serveKeepstoreMounts()
 466         s.stub.serveKeepstoreIndexFoo4Bar1()
 467         trashReqs := s.stub.serveKeepstoreTrash()
 468         pullReqs := s.stub.serveKeepstorePull()
 469         srv := s.newServer(&opts)
 470         bal, err := srv.runOnce()
 471         c.Check(err, check.IsNil)
 472         c.Check(trashReqs.Count(), check.Equals, 8)
 473         c.Check(pullReqs.Count(), check.Equals, 4)
 474         // "foo" block is overreplicated by 2
 475         c.Check(bal.stats.trashes, check.Equals, 2)
 476         // "bar" block is underreplicated by 1, and its only copy is
 477         // in a poor rendezvous position
 478         c.Check(bal.stats.pulls, check.Equals, 2)
 479
 480         lost, err := ioutil.ReadFile(s.config.Collections.BlobMissingReport)
 481         c.Assert(err, check.IsNil)
 482         c.Check(string(lost), check.Not(check.Matches), `(?ms).*acbd18db4cc2f85cedef654fccc4a4d8.*`)
 483
 484         buf, err := s.getMetrics(c, srv)
 485         c.Check(err, check.IsNil)
 486         bufstr := buf.String()
 487         c.Check(bufstr, check.Matches, `(?ms).*\narvados_keep_total_bytes 15\n.*`)
 488         c.Check(bufstr, check.Matches, `(?ms).*\narvados_keepbalance_changeset_compute_seconds_sum [0-9\.]+\n.*`)
 489         c.Check(bufstr, check.Matches, `(?ms).*\narvados_keepbalance_changeset_compute_seconds_count 1\n.*`)
 490         c.Check(bufstr, check.Matches, `(?ms).*\narvados_keep_dedup_byte_ratio [1-9].*`)
 491         c.Check(bufstr, check.Matches, `(?ms).*\narvados_keep_dedup_block_ratio [1-9].*`)
 492 }
 493
 494 func (s *runSuite) TestRunForever(c *check.C) {
 495         s.config.ManagementToken = "xyzzy"
 496         opts := RunOptions{
 497                 CommitPulls: true,
 498                 CommitTrash: true,
 499                 Logger:      ctxlog.TestLogger(c),
 500                 Dumper:      ctxlog.TestLogger(c),
 501         }
 502         s.stub.serveCurrentUserAdmin()
 503         s.stub.serveFooBarFileCollections()
 504         s.stub.serveKeepServices(stubServices)
 505         s.stub.serveKeepstoreMounts()
 506         s.stub.serveKeepstoreIndexFoo4Bar1()
 507         trashReqs := s.stub.serveKeepstoreTrash()
 508         pullReqs := s.stub.serveKeepstorePull()
 509
 510         stop := make(chan interface{})
 511         s.config.Collections.BalancePeriod = arvados.Duration(time.Millisecond)
 512         srv := s.newServer(&opts)
 513
 514         done := make(chan bool)
 515         go func() {
 516                 srv.runForever(stop)
 517                 close(done)
 518         }()
 519
 520         // Each run should send 4 pull lists + 4 trash lists. The
 521         // first run should also send 4 empty trash lists at
 522         // startup. We should complete all four runs in much less than
 523         // a second.
 524         for t0 := time.Now(); pullReqs.Count() < 16 && time.Since(t0) < 10*time.Second; {
 525                 time.Sleep(time.Millisecond)
 526         }
 527         stop <- true
 528         <-done
 529         c.Check(pullReqs.Count() >= 16, check.Equals, true)
 530         c.Check(trashReqs.Count(), check.Equals, pullReqs.Count()+4)
 531
 532         buf, err := s.getMetrics(c, srv)
 533         c.Check(err, check.IsNil)
 534         c.Check(buf, check.Matches, `(?ms).*\narvados_keepbalance_changeset_compute_seconds_count `+fmt.Sprintf("%d", pullReqs.Count()/4)+`\n.*`)
 535 }
 536
 537 func (s *runSuite) getMetrics(c *check.C, srv *Server) (*bytes.Buffer, error) {
 538         mfs, err := srv.Metrics.reg.Gather()
 539         if err != nil {
 540                 return nil, err
 541         }
 542
 543         var buf bytes.Buffer
 544         for _, mf := range mfs {
 545                 if _, err := expfmt.MetricFamilyToText(&buf, mf); err != nil {
 546                         return nil, err
 547                 }
 548         }
 549
 550         return &buf, nil
 551 }