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4 Commits

Author SHA1 Message Date
Christian Schwarz f61295f76c build: Makefile: zsh completions (fixup 0920a40751)
refs #308
fixes #309
2020-04-18 21:36:48 +02:00
Christian Schwarz 0920a40751 reorganize shell completion generator command + support zsh
fixes #308
2020-04-18 19:23:04 +02:00
Christian Schwarz e0b5bd75f8 endpoint: refactor, fix stale holds on initial replication failure, zfs-abstractions subcmd, more efficient ZFS queries
The motivation for this recatoring are based on two independent issues:

- @JMoVS found that the changes merged as part of #259 slowed his OS X
  based installation down significantly.
  Analysis of the zfs command logging introduced in #296 showed that
  `zfs holds` took most of the execution time, and they pointed out
  that not all of those `zfs holds` invocations were actually necessary.
  I.e.: zrepl was inefficient about retrieving information from ZFS.

- @InsanePrawn found that failures on initial replication would lead
  to step holds accumulating on the sending side, i.e. they would never
  be cleaned up in the HintMostRecentCommonAncestor RPC handler.
  That was because we only sent that RPC if there was a most recent
  common ancestor detected during replication planning.
  @InsanePrawn prototyped an implementation of a `zrepl zfs-abstractions release`
  command to mitigate the situation.
  As part of that development work and back-and-forth with @problame,
  it became evident that the abstractions that #259 built on top of
  zfs in package endpoint (step holds, replication cursor,
  last-received-hold), were not well-represented for re-use in the
  `zrepl zfs-abstractions release` subocommand prototype.

This commit refactors package endpoint to address both of these issues:

- endpoint abstractions now share an interface `Abstraction` that, among
  other things, provides a uniform `Destroy()` method.
  However, that method should not be destroyed directly but instead
  the package-level `BatchDestroy` function should be used in order
  to allow for a migration to zfs channel programs in the future.

- endpoint now has a query facitilty (`ListAbstractions`) which is
  used to find on-disk
    - step holds and bookmarks
    - replication cursors (v1, v2)
    - last-received-holds
  By describing the query in a struct, we can centralized the retrieval
  of information via the ZFS CLI and only have to be clever once.
  We are "clever" in the following ways:
  - When asking for hold-based abstractions, we only run `zfs holds` on
    snapshot that have `userrefs` > 0
    - To support this functionality, add field `UserRefs` to zfs.FilesystemVersion
      and retrieve it anywhere we retrieve zfs.FilesystemVersion from ZFS.
  - When asking only for bookmark-based abstractions, we only run
    `zfs list -t bookmark`, not with snapshots.
  - Currently unused (except for CLI) per-filesystem concurrent lookup
  - Option to only include abstractions with CreateTXG in a specified range

- refactor `endpoint`'s various ZFS info  retrieval methods to use
  `ListAbstractions`

- rename the `zrepl holds list` command to `zrepl zfs-abstractions list`
- make `zrepl zfs-abstractions list` consume endpoint.ListAbstractions

- Add a `ListStale` method which, given a query template,
  lists stale holds and bookmarks.
  - it uses replication cursor has different modes
- the new `zrepl zfs-abstractions release-{all,stale}` commands can be used
  to remove abstractions of package endpoint

- Adjust HintMostRecentCommonAncestor RPC for stale-holds cleanup:
    - send it also if no most recent common ancestor exists between sender and receiver
    - have the sender clean up its abstractions when it receives the RPC
      with no most recent common ancestor, using `ListStale`
    - Due to changed semantics, bump the protocol version.

- Adjust HintMostRecentCommonAncestor RPC for performance problems
  encountered by @JMoVS
    - by default, per (job,fs)-combination, only consider cleaning
      step holds in the createtxg range
      `[last replication cursor,conservatively-estimated-receive-side-version)`
    - this behavior ensures resumability at cost proportional to the
      time that replication was donw
    - however, as explained in a comment, we might leak holds if
      the zrepl daemon stops running
    - that  trade-off is acceptable because in the presumably rare
      this might happen the user has two tools at their hand:
    - Tool 1: run `zrepl zfs-abstractions release-stale`
    - Tool 2: use env var `ZREPL_ENDPOINT_SENDER_HINT_MOST_RECENT_STEP_HOLD_CLEANUP_MODE`
      to adjust the lower bound of the createtxg range (search for it in the code).
      The env var can also be used to disable hold-cleanup on the
      send-side entirely.

supersedes closes #293
supersedes closes #282
fixes #280
fixes #278

Additionaly, we fixed a couple of bugs:

- zfs: fix half-nil error reporting of dataset-does-not-exist for ZFSListChan and ZFSBookmark

- endpoint: Sender's `HintMostRecentCommonAncestor` handler would not
  check whether access to the specified filesystem was allowed.
2020-04-18 12:26:03 +02:00
Christian Schwarz 96e188d7c4 zfscmd: fix nil deref in waitPostLogging when command was killed
fixes #301
2020-04-08 00:26:56 +02:00
18 changed files with 248 additions and 129 deletions
+8 -3
View File
@@ -65,6 +65,7 @@ wrapup-and-checksum:
-acf $(NOARCH_TARBALL) \
$(ARTIFACTDIR)/docs/html \
$(ARTIFACTDIR)/bash_completion \
$(ARTIFACTDIR)/_zrepl.zsh_completion \
$(ARTIFACTDIR)/go_env.txt \
dist \
config/samples
@@ -159,7 +160,7 @@ platformtest: # do not track dependency on platformtest-bin to allow build of pl
$(ZREPL_PLATFORMTEST_ARGS)
##################### NOARCH #####################
.PHONY: noarch $(ARTIFACTDIR)/bash_completion $(ARTIFACTDIR)/go_env.txt docs docs-clean
.PHONY: noarch $(ARTIFACTDIR)/bash_completion $(ARTIFACTDIR)/_zrepl.zsh_completion $(ARTIFACTDIR)/go_env.txt docs docs-clean
$(ARTIFACTDIR):
@@ -167,12 +168,16 @@ $(ARTIFACTDIR):
$(ARTIFACTDIR)/docs: $(ARTIFACTDIR)
mkdir -p "$@"
noarch: $(ARTIFACTDIR)/bash_completion $(ARTIFACTDIR)/go_env.txt docs
noarch: $(ARTIFACTDIR)/bash_completion $(ARTIFACTDIR)/_zrepl.zsh_completion $(ARTIFACTDIR)/go_env.txt docs
# pass
$(ARTIFACTDIR)/bash_completion:
$(MAKE) zrepl-bin GOOS=$(GOHOSTOS) GOARCH=$(GOHOSTARCH)
artifacts/zrepl-$(GOHOSTOS)-$(GOHOSTARCH) bashcomp "$@"
artifacts/zrepl-$(GOHOSTOS)-$(GOHOSTARCH) gencompletion bash "$@"
$(ARTIFACTDIR)/_zrepl.zsh_completion:
$(MAKE) zrepl-bin GOOS=$(GOHOSTOS) GOARCH=$(GOHOSTARCH)
artifacts/zrepl-$(GOHOSTOS)-$(GOHOSTARCH) gencompletion zsh "$@"
$(ARTIFACTDIR)/go_env.txt:
$(GO_ENV_VARS) $(GO) env > $@
+36 -10
View File
@@ -19,9 +19,38 @@ var rootCmd = &cobra.Command{
Short: "One-stop ZFS replication solution",
}
var bashcompCmd = &cobra.Command{
Use: "bashcomp path/to/out/file",
Short: "generate bash completions",
func init() {
rootCmd.PersistentFlags().StringVar(&rootArgs.configPath, "config", "", "config file path")
}
var genCompletionCmd = &cobra.Command{
Use: "gencompletion",
Short: "generate shell auto-completions",
}
type completionCmdInfo struct {
genFunc func(outpath string) error
help string
}
var completionCmdMap = map[string]completionCmdInfo{
"zsh": {
rootCmd.GenZshCompletionFile,
" save to file `_zrepl` in your zsh's $fpath",
},
"bash": {
rootCmd.GenBashCompletionFile,
" save to a path and source that path in your .bashrc",
},
}
func init() {
for sh, info := range completionCmdMap {
sh, info := sh, info
genCompletionCmd.AddCommand(&cobra.Command{
Use: fmt.Sprintf("%s path/to/out/file", sh),
Short: fmt.Sprintf("generate %s completions", sh),
Example: info.help,
Run: func(cmd *cobra.Command, args []string) {
if len(args) != 1 {
fmt.Fprintf(os.Stderr, "specify exactly one positional agument\n")
@@ -31,17 +60,14 @@ var bashcompCmd = &cobra.Command{
}
os.Exit(1)
}
if err := rootCmd.GenBashCompletionFile(args[0]); err != nil {
fmt.Fprintf(os.Stderr, "error generating bash completion: %s", err)
if err := info.genFunc(args[0]); err != nil {
fmt.Fprintf(os.Stderr, "error generating %s completion: %s", sh, err)
os.Exit(1)
}
},
Hidden: true,
})
}
func init() {
rootCmd.PersistentFlags().StringVar(&rootArgs.configPath, "config", "", "config file path")
rootCmd.AddCommand(bashcompCmd)
rootCmd.AddCommand(genCompletionCmd)
}
type Subcommand struct {
-14
View File
@@ -1,14 +0,0 @@
package client
import "github.com/zrepl/zrepl/cli"
var holdsCmdCreate = &cli.Subcommand{
Use: "create",
NoRequireConfig: true,
Short: `create zrepl-managed holds and boomkmarks (for debugging & development only!)`,
SetupSubcommands: func() []*cli.Subcommand {
return []*cli.Subcommand{
holdsCmdCreateStepHold,
}
},
}
+10 -10
View File
@@ -14,15 +14,15 @@ import (
)
var (
HoldsCmd = &cli.Subcommand{
Use: "holds",
Short: "manage holds & step bookmarks",
ZFSAbstractionsCmd = &cli.Subcommand{
Use: "zfs-abstraction",
Short: "manage abstractions that zrepl builds on top of ZFS",
SetupSubcommands: func() []*cli.Subcommand {
return []*cli.Subcommand{
holdsCmdList,
holdsCmdReleaseAll,
holdsCmdReleaseStale,
holdsCmdCreate,
zabsCmdList,
zabsCmdReleaseAll,
zabsCmdReleaseStale,
zabsCmdCreate,
}
},
}
@@ -30,7 +30,7 @@ var (
// a common set of CLI flags that map to the fields of an
// endpoint.ListZFSHoldsAndBookmarksQuery
type holdsFilterFlags struct {
type zabsFilterFlags struct {
Filesystems FilesystemsFilterFlag
Job JobIDFlag
Types AbstractionTypesFlag
@@ -38,7 +38,7 @@ type holdsFilterFlags struct {
}
// produce a query from the CLI flags
func (f holdsFilterFlags) Query() (endpoint.ListZFSHoldsAndBookmarksQuery, error) {
func (f zabsFilterFlags) Query() (endpoint.ListZFSHoldsAndBookmarksQuery, error) {
q := endpoint.ListZFSHoldsAndBookmarksQuery{
FS: f.Filesystems.FlagValue(),
What: f.Types.FlagValue(),
@@ -48,7 +48,7 @@ func (f holdsFilterFlags) Query() (endpoint.ListZFSHoldsAndBookmarksQuery, error
return q, q.Validate()
}
func (f *holdsFilterFlags) registerHoldsFilterFlags(s *pflag.FlagSet, verb string) {
func (f *zabsFilterFlags) registerZabsFilterFlags(s *pflag.FlagSet, verb string) {
// Note: the default value is defined in the .FlagValue methods
s.Var(&f.Filesystems, "fs", fmt.Sprintf("only %s holds on the specified filesystem [default: all filesystems] [comma-separated list of <dataset-pattern>:<ok|!> pairs]", verb))
s.Var(&f.Job, "job", fmt.Sprintf("only %s holds created by the specified job [default: any job]", verb))
+14
View File
@@ -0,0 +1,14 @@
package client
import "github.com/zrepl/zrepl/cli"
var zabsCmdCreate = &cli.Subcommand{
Use: "create",
NoRequireConfig: true,
Short: `create zrepl ZFS abstractions (mostly useful for debugging & development, users should not need to use this command)`,
SetupSubcommands: func() []*cli.Subcommand {
return []*cli.Subcommand{
zabsCmdCreateStepHold,
}
},
}
@@ -12,28 +12,28 @@ import (
"github.com/zrepl/zrepl/zfs"
)
var holdsCreateStepHoldFlags struct {
var zabsCreateStepHoldFlags struct {
target string
jobid JobIDFlag
}
var holdsCmdCreateStepHold = &cli.Subcommand{
var zabsCmdCreateStepHold = &cli.Subcommand{
Use: "step",
Run: doHoldsCreateStep,
Run: doZabsCreateStep,
NoRequireConfig: true,
Short: `create a step hold or bookmark`,
SetupFlags: func(f *pflag.FlagSet) {
f.StringVarP(&holdsCreateStepHoldFlags.target, "target", "t", "", "snapshot to be held / bookmark to be held")
f.VarP(&holdsCreateStepHoldFlags.jobid, "jobid", "j", "jobid for which the hold is installed")
f.StringVarP(&zabsCreateStepHoldFlags.target, "target", "t", "", "snapshot to be held / bookmark to be held")
f.VarP(&zabsCreateStepHoldFlags.jobid, "jobid", "j", "jobid for which the hold is installed")
},
}
func doHoldsCreateStep(sc *cli.Subcommand, args []string) error {
func doZabsCreateStep(sc *cli.Subcommand, args []string) error {
if len(args) > 0 {
return errors.New("subcommand takes no arguments")
}
f := &holdsCreateStepHoldFlags
f := &zabsCreateStepHoldFlags
fs, _, _, err := zfs.DecomposeVersionString(f.target)
if err != nil {
@@ -16,23 +16,23 @@ import (
"github.com/zrepl/zrepl/util/chainlock"
)
var holdsListFlags struct {
Filter holdsFilterFlags
var zabsListFlags struct {
Filter zabsFilterFlags
Json bool
}
var holdsCmdList = &cli.Subcommand{
var zabsCmdList = &cli.Subcommand{
Use: "list",
Run: doHoldsList,
Short: `list zrepl ZFS abstractions`,
Run: doZabsList,
NoRequireConfig: true,
Short: "list holds and bookmarks",
SetupFlags: func(f *pflag.FlagSet) {
holdsListFlags.Filter.registerHoldsFilterFlags(f, "list")
f.BoolVar(&holdsListFlags.Json, "json", false, "emit JSON")
zabsListFlags.Filter.registerZabsFilterFlags(f, "list")
f.BoolVar(&zabsListFlags.Json, "json", false, "emit JSON")
},
}
func doHoldsList(sc *cli.Subcommand, args []string) error {
func doZabsList(sc *cli.Subcommand, args []string) error {
var err error
ctx := context.Background()
@@ -40,7 +40,7 @@ func doHoldsList(sc *cli.Subcommand, args []string) error {
return errors.New("this subcommand takes no positional arguments")
}
q, err := holdsListFlags.Filter.Query()
q, err := zabsListFlags.Filter.Query()
if err != nil {
return errors.Wrap(err, "invalid filter specification on command line")
}
@@ -62,7 +62,7 @@ func doHoldsList(sc *cli.Subcommand, args []string) error {
for a := range abstractions {
func() {
defer line.Lock().Unlock()
if holdsListFlags.Json {
if zabsListFlags.Json {
enc.SetIndent("", " ")
if err := enc.Encode(abstractions); err != nil {
panic(err)
@@ -15,35 +15,35 @@ import (
)
// shared between release-all and release-step
var holdsReleaseFlags struct {
Filter holdsFilterFlags
var zabsReleaseFlags struct {
Filter zabsFilterFlags
Json bool
DryRun bool
}
func registerHoldsReleaseFlags(s *pflag.FlagSet) {
holdsReleaseFlags.Filter.registerHoldsFilterFlags(s, "release")
s.BoolVar(&holdsReleaseFlags.Json, "json", false, "emit json instead of pretty-printed")
s.BoolVar(&holdsReleaseFlags.DryRun, "dry-run", false, "do a dry-run")
func registerZabsReleaseFlags(s *pflag.FlagSet) {
zabsReleaseFlags.Filter.registerZabsFilterFlags(s, "release")
s.BoolVar(&zabsReleaseFlags.Json, "json", false, "emit json instead of pretty-printed")
s.BoolVar(&zabsReleaseFlags.DryRun, "dry-run", false, "do a dry-run")
}
var holdsCmdReleaseAll = &cli.Subcommand{
var zabsCmdReleaseAll = &cli.Subcommand{
Use: "release-all",
Run: doHoldsReleaseAll,
Run: doZabsReleaseAll,
NoRequireConfig: true,
Short: `(DANGEROUS) release all zrepl-managed holds and bookmarks, mostly useful for uninstalling zrepl`,
SetupFlags: registerHoldsReleaseFlags,
Short: `(DANGEROUS) release ALL zrepl ZFS abstractions (mostly useful for uninstalling zrepl completely or for "de-zrepl-ing" a filesystem)`,
SetupFlags: registerZabsReleaseFlags,
}
var holdsCmdReleaseStale = &cli.Subcommand{
var zabsCmdReleaseStale = &cli.Subcommand{
Use: "release-stale",
Run: doHoldsReleaseStale,
Run: doZabsReleaseStale,
NoRequireConfig: true,
Short: `release stale zrepl-managed holds and boomkarks (useful if zrepl has a bug and doesn't do it by itself)`,
SetupFlags: registerHoldsReleaseFlags,
Short: `release stale zrepl ZFS abstractions (useful if zrepl has a bug and does not do it by itself)`,
SetupFlags: registerZabsReleaseFlags,
}
func doHoldsReleaseAll(sc *cli.Subcommand, args []string) error {
func doZabsReleaseAll(sc *cli.Subcommand, args []string) error {
var err error
ctx := context.Background()
@@ -51,7 +51,7 @@ func doHoldsReleaseAll(sc *cli.Subcommand, args []string) error {
return errors.New("this subcommand takes no positional arguments")
}
q, err := holdsReleaseFlags.Filter.Query()
q, err := zabsReleaseFlags.Filter.Query()
if err != nil {
return errors.Wrap(err, "invalid filter specification on command line")
}
@@ -65,10 +65,10 @@ func doHoldsReleaseAll(sc *cli.Subcommand, args []string) error {
// proceed anyways with rest of abstractions
}
return doHoldsRelease_Common(ctx, abstractions)
return doZabsRelease_Common(ctx, abstractions)
}
func doHoldsReleaseStale(sc *cli.Subcommand, args []string) error {
func doZabsReleaseStale(sc *cli.Subcommand, args []string) error {
var err error
ctx := context.Background()
@@ -77,7 +77,7 @@ func doHoldsReleaseStale(sc *cli.Subcommand, args []string) error {
return errors.New("this subcommand takes no positional arguments")
}
q, err := holdsReleaseFlags.Filter.Query()
q, err := zabsReleaseFlags.Filter.Query()
if err != nil {
return errors.Wrap(err, "invalid filter specification on command line")
}
@@ -87,13 +87,13 @@ func doHoldsReleaseStale(sc *cli.Subcommand, args []string) error {
return err // context clear by invocation of command
}
return doHoldsRelease_Common(ctx, stalenessInfo.Stale)
return doZabsRelease_Common(ctx, stalenessInfo.Stale)
}
func doHoldsRelease_Common(ctx context.Context, destroy []endpoint.Abstraction) error {
func doZabsRelease_Common(ctx context.Context, destroy []endpoint.Abstraction) error {
if holdsReleaseFlags.DryRun {
if holdsReleaseFlags.Json {
if zabsReleaseFlags.DryRun {
if zabsReleaseFlags.Json {
m, err := json.MarshalIndent(destroy, "", " ")
if err != nil {
panic(err)
@@ -121,7 +121,7 @@ func doHoldsRelease_Common(ctx context.Context, destroy []endpoint.Abstraction)
for res := range outcome {
hadErr = hadErr || res.DestroyErr != nil
if holdsReleaseFlags.Json {
if zabsReleaseFlags.Json {
err := enc.Encode(res)
if err != nil {
colorErr.Fprintf(os.Stderr, "cannot marshal there were errors in destroying the abstractions")
+2
View File
@@ -62,7 +62,9 @@ Actual changelog:
* |bugfix| |docs| snapshotting: clarify sync-up behavior and warn about filesystems
that will not be snapshotted until the sync-up phase is over
* |docs| Document new replication features in the :ref:`config overview <overview-how-replication-works>` and :repomasterlink:`replication/design.md`.
* |feature| documented subcommand to generate ``bash`` and ``zsh`` completions
* **[MAINTAINER NOTICE]** New platform tests in this version, please make sure you run them for your distro!
* **[MAINTAINER NOTICE]** Please add the shell completions to the zrepl packages.
0.2.1
-----
+2 -2
View File
@@ -38,8 +38,8 @@ CLI Overview
* - ``zrepl migrate``
- | perform on-disk state / ZFS property migrations
| (see :ref:`changelog <changelog>` for details)
* - ``zrepl holds``
- list and remove holds and step bookmarks created by zrepl (see :ref:`overview <replication-cursor-and-last-received-hold>` )
* - ``zrepl zfs-abstractions``
- list and remove zrepl's abstractions on top of ZFS, e.g. holds and step bookmarks (see :ref:`overview <replication-cursor-and-last-received-hold>` )
.. _usage-zrepl-daemon:
+4 -4
View File
@@ -150,11 +150,11 @@ func (p *Sender) HintMostRecentCommonAncestor(ctx context.Context, r *pdu.HintMo
}
// take care of stale step holds
log.WithField("step-holds-cleanup-mode", hintMostRecentCommonAncestorStepCleanupMode).
log.WithField("step-holds-cleanup-mode", senderHintMostRecentCommonAncestorStepCleanupMode).
Debug("taking care of possibly stale step holds")
doStepCleanup := false
var stepCleanupSince *CreateTXGRangeBound
switch hintMostRecentCommonAncestorStepCleanupMode {
switch senderHintMostRecentCommonAncestorStepCleanupMode {
case StepCleanupNoCleanup:
doStepCleanup = false
case StepCleanupRangeSinceUnbounded:
@@ -180,7 +180,7 @@ func (p *Sender) HintMostRecentCommonAncestor(ctx context.Context, r *pdu.HintMo
}
}
default:
panic(hintMostRecentCommonAncestorStepCleanupMode)
panic(senderHintMostRecentCommonAncestorStepCleanupMode)
}
if !doStepCleanup {
log.Info("skipping cleanup of prior invocations' step holds due to environment variable setting")
@@ -218,7 +218,7 @@ func (m *HintMostRecentCommonAncestorStepCleanupMode) Set(s string) error {
return nil
}
var hintMostRecentCommonAncestorStepCleanupMode = *envconst.Var("ZREPL_ENDPOINT_HINT_MOST_RECENT_STEP_HOLD_CLEANUP_MODE", &StepCleanupRangeSinceReplicationCursor).(*HintMostRecentCommonAncestorStepCleanupMode)
var senderHintMostRecentCommonAncestorStepCleanupMode = *envconst.Var("ZREPL_ENDPOINT_SENDER_HINT_MOST_RECENT_STEP_HOLD_CLEANUP_MODE", &StepCleanupRangeSinceReplicationCursor).(*HintMostRecentCommonAncestorStepCleanupMode)
var maxConcurrentZFSSendSemaphore = semaphore.New(envconst.Int64("ZREPL_ENDPOINT_MAX_CONCURRENT_SEND", 10))
+1 -1
View File
@@ -17,7 +17,7 @@ func init() {
cli.AddSubcommand(client.PprofCmd)
cli.AddSubcommand(client.TestCmd)
cli.AddSubcommand(client.MigrateCmd)
cli.AddSubcommand(client.HoldsCmd)
cli.AddSubcommand(client.ZFSAbstractionsCmd)
}
func main() {
+26 -1
View File
@@ -18,7 +18,32 @@ Hence, when trying to map algorithm to implementation, use the code in package `
* the recv-side fs doesn't get newer snapshots than `to` in the meantime
* guaranteed because the zrepl model of the receiver assumes ownership of the filesystems it receives into
* if that assumption is broken, future replication attempts will fail with a conflict
* The [Algorithm for Planning and Executing Replication of an Filesystems](#zrepl-algo-filesystem) is a design draft and not used
* The [Algorithm for Planning and Executing Replication of an Filesystems](#zrepl-algo-filesystem) is a design draft and not used.
However, there were some noteworthy lessons learned when implementing the algorithm for a single step:
* In order to avoid leaking `step-hold`s and `step-bookmarks`, if the replication planner is invoked a second time after a replication step (either initial or incremental) has been attempted but failed to completed, the replication planner must
* A) either guarantee that it will resume that replication step, and continue as if nothing happened or
* B) release the step holds and bookmarks and clear the partially received state on the sending side.
* Option A is what we want to do: we use the step algorithm to achieve resumability in the first place!
* Option B is not done by zrepl except if the sending side doesn't support resuming.
In that case however, we need not release any holds since the behavior is to re-start the send
from the beginning.
* However, there is one **edge-case to Option A for initial replication**:
* If initial replication "`full a`" fails without leaving resumable state, the step holds on the sending side are still present, which makes sense because
* a) we want resumability and
* b) **the sending side cannot immediately be informed post-failure whether the initial replication left any state that would mandate keeping the step hold**, because the network connection might have failed.
* Thus, the sending side must keep the step hold for "`full a`" until it knows more.
* In the current implementation, it knows more when the next replication attempt is made, the planner is invoked, the diffing algorithm run, and the `HintMostRecentCommonAncestor` RPC is sent by the active side, communicating the most recent common version shared betwen sender and receiver.
* At this point, the sender can safely throw away any step holds with CreateTXG's older than that version.
* **The `step-hold`, `step-bookmark`, `last-received-hold` and `replication-cursor` abstractions are currently local concepts of package `endpoint` and not part of the replication protocol**
* This is not necessarilty the best design decision and should be revisited some point:
* The (quite expensive) `HintMostRecentCommonAncestor` RPC impl on the sender would not be necessary if step holds were part of the replication protocol:
* We only need the `HintMostRecentCommonAncestor` info for the aforementioned edge-case during initial replication, where the receive is aborted without any partial received state being stored on the receiver (due to network failure, wrong zfs invocation, bad permissions, etc):
* **The replication planner does not know about the step holds, thus it cannot deterministically pick up where it left of (right at the start of the last failing initial replication).**
* Instead, it will seem like no prior invocation happened at all, and it will apply its policy for initial replication to pick a new `full b != full a`, **thereby leaking the step holds of `full a`**.
* In contrast, if the replication planner created the step holds and knew about them, it could use the step holds as an indicator where it left off and re-start from there (of course asserting that the thereby inferred step is compatible with the state of the receiving side).
* (What we do in zrepl right now is to hard-code the initial replication policy, and hard-code that assumption in `endpoint.ListStale` as well.)
* The cummulative cleanup done in `HintMostRecentCommonAncestor` provides a nice self-healing aspect, though.
* We also have [Notes on Planning and Executing Replication of Multiple Filesystems](#zrepl-algo-multiple-filesystems-notes)
---
+36 -27
View File
@@ -46,7 +46,7 @@ func (x Tri) String() string {
return proto.EnumName(Tri_name, int32(x))
}
func (Tri) EnumDescriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{0}
return fileDescriptor_pdu_e59763dc61674a79, []int{0}
}
type FilesystemVersion_VersionType int32
@@ -69,7 +69,7 @@ func (x FilesystemVersion_VersionType) String() string {
return proto.EnumName(FilesystemVersion_VersionType_name, int32(x))
}
func (FilesystemVersion_VersionType) EnumDescriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{5, 0}
return fileDescriptor_pdu_e59763dc61674a79, []int{5, 0}
}
type ListFilesystemReq struct {
@@ -82,7 +82,7 @@ func (m *ListFilesystemReq) Reset() { *m = ListFilesystemReq{} }
func (m *ListFilesystemReq) String() string { return proto.CompactTextString(m) }
func (*ListFilesystemReq) ProtoMessage() {}
func (*ListFilesystemReq) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{0}
return fileDescriptor_pdu_e59763dc61674a79, []int{0}
}
func (m *ListFilesystemReq) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_ListFilesystemReq.Unmarshal(m, b)
@@ -113,7 +113,7 @@ func (m *ListFilesystemRes) Reset() { *m = ListFilesystemRes{} }
func (m *ListFilesystemRes) String() string { return proto.CompactTextString(m) }
func (*ListFilesystemRes) ProtoMessage() {}
func (*ListFilesystemRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{1}
return fileDescriptor_pdu_e59763dc61674a79, []int{1}
}
func (m *ListFilesystemRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_ListFilesystemRes.Unmarshal(m, b)
@@ -154,7 +154,7 @@ func (m *Filesystem) Reset() { *m = Filesystem{} }
func (m *Filesystem) String() string { return proto.CompactTextString(m) }
func (*Filesystem) ProtoMessage() {}
func (*Filesystem) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{2}
return fileDescriptor_pdu_e59763dc61674a79, []int{2}
}
func (m *Filesystem) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_Filesystem.Unmarshal(m, b)
@@ -213,7 +213,7 @@ func (m *ListFilesystemVersionsReq) Reset() { *m = ListFilesystemVersion
func (m *ListFilesystemVersionsReq) String() string { return proto.CompactTextString(m) }
func (*ListFilesystemVersionsReq) ProtoMessage() {}
func (*ListFilesystemVersionsReq) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{3}
return fileDescriptor_pdu_e59763dc61674a79, []int{3}
}
func (m *ListFilesystemVersionsReq) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_ListFilesystemVersionsReq.Unmarshal(m, b)
@@ -251,7 +251,7 @@ func (m *ListFilesystemVersionsRes) Reset() { *m = ListFilesystemVersion
func (m *ListFilesystemVersionsRes) String() string { return proto.CompactTextString(m) }
func (*ListFilesystemVersionsRes) ProtoMessage() {}
func (*ListFilesystemVersionsRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{4}
return fileDescriptor_pdu_e59763dc61674a79, []int{4}
}
func (m *ListFilesystemVersionsRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_ListFilesystemVersionsRes.Unmarshal(m, b)
@@ -293,7 +293,7 @@ func (m *FilesystemVersion) Reset() { *m = FilesystemVersion{} }
func (m *FilesystemVersion) String() string { return proto.CompactTextString(m) }
func (*FilesystemVersion) ProtoMessage() {}
func (*FilesystemVersion) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{5}
return fileDescriptor_pdu_e59763dc61674a79, []int{5}
}
func (m *FilesystemVersion) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_FilesystemVersion.Unmarshal(m, b)
@@ -371,7 +371,7 @@ func (m *SendReq) Reset() { *m = SendReq{} }
func (m *SendReq) String() string { return proto.CompactTextString(m) }
func (*SendReq) ProtoMessage() {}
func (*SendReq) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{6}
return fileDescriptor_pdu_e59763dc61674a79, []int{6}
}
func (m *SendReq) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_SendReq.Unmarshal(m, b)
@@ -445,7 +445,7 @@ func (m *Property) Reset() { *m = Property{} }
func (m *Property) String() string { return proto.CompactTextString(m) }
func (*Property) ProtoMessage() {}
func (*Property) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{7}
return fileDescriptor_pdu_e59763dc61674a79, []int{7}
}
func (m *Property) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_Property.Unmarshal(m, b)
@@ -496,7 +496,7 @@ func (m *SendRes) Reset() { *m = SendRes{} }
func (m *SendRes) String() string { return proto.CompactTextString(m) }
func (*SendRes) ProtoMessage() {}
func (*SendRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{8}
return fileDescriptor_pdu_e59763dc61674a79, []int{8}
}
func (m *SendRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_SendRes.Unmarshal(m, b)
@@ -548,7 +548,7 @@ func (m *SendCompletedReq) Reset() { *m = SendCompletedReq{} }
func (m *SendCompletedReq) String() string { return proto.CompactTextString(m) }
func (*SendCompletedReq) ProtoMessage() {}
func (*SendCompletedReq) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{9}
return fileDescriptor_pdu_e59763dc61674a79, []int{9}
}
func (m *SendCompletedReq) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_SendCompletedReq.Unmarshal(m, b)
@@ -585,7 +585,7 @@ func (m *SendCompletedRes) Reset() { *m = SendCompletedRes{} }
func (m *SendCompletedRes) String() string { return proto.CompactTextString(m) }
func (*SendCompletedRes) ProtoMessage() {}
func (*SendCompletedRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{10}
return fileDescriptor_pdu_e59763dc61674a79, []int{10}
}
func (m *SendCompletedRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_SendCompletedRes.Unmarshal(m, b)
@@ -608,7 +608,7 @@ var xxx_messageInfo_SendCompletedRes proto.InternalMessageInfo
type ReceiveReq struct {
Filesystem string `protobuf:"bytes,1,opt,name=Filesystem,proto3" json:"Filesystem,omitempty"`
To *FilesystemVersion `protobuf:"bytes,2,opt,name=To,proto3" json:"To,omitempty"`
// If true, the receiver should clear the resume token before perfoming the
// If true, the receiver should clear the resume token before performing the
// zfs recv of the stream in the request
ClearResumeToken bool `protobuf:"varint,3,opt,name=ClearResumeToken,proto3" json:"ClearResumeToken,omitempty"`
XXX_NoUnkeyedLiteral struct{} `json:"-"`
@@ -620,7 +620,7 @@ func (m *ReceiveReq) Reset() { *m = ReceiveReq{} }
func (m *ReceiveReq) String() string { return proto.CompactTextString(m) }
func (*ReceiveReq) ProtoMessage() {}
func (*ReceiveReq) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{11}
return fileDescriptor_pdu_e59763dc61674a79, []int{11}
}
func (m *ReceiveReq) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_ReceiveReq.Unmarshal(m, b)
@@ -671,7 +671,7 @@ func (m *ReceiveRes) Reset() { *m = ReceiveRes{} }
func (m *ReceiveRes) String() string { return proto.CompactTextString(m) }
func (*ReceiveRes) ProtoMessage() {}
func (*ReceiveRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{12}
return fileDescriptor_pdu_e59763dc61674a79, []int{12}
}
func (m *ReceiveRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_ReceiveRes.Unmarshal(m, b)
@@ -704,7 +704,7 @@ func (m *DestroySnapshotsReq) Reset() { *m = DestroySnapshotsReq{} }
func (m *DestroySnapshotsReq) String() string { return proto.CompactTextString(m) }
func (*DestroySnapshotsReq) ProtoMessage() {}
func (*DestroySnapshotsReq) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{13}
return fileDescriptor_pdu_e59763dc61674a79, []int{13}
}
func (m *DestroySnapshotsReq) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_DestroySnapshotsReq.Unmarshal(m, b)
@@ -750,7 +750,7 @@ func (m *DestroySnapshotRes) Reset() { *m = DestroySnapshotRes{} }
func (m *DestroySnapshotRes) String() string { return proto.CompactTextString(m) }
func (*DestroySnapshotRes) ProtoMessage() {}
func (*DestroySnapshotRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{14}
return fileDescriptor_pdu_e59763dc61674a79, []int{14}
}
func (m *DestroySnapshotRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_DestroySnapshotRes.Unmarshal(m, b)
@@ -795,7 +795,7 @@ func (m *DestroySnapshotsRes) Reset() { *m = DestroySnapshotsRes{} }
func (m *DestroySnapshotsRes) String() string { return proto.CompactTextString(m) }
func (*DestroySnapshotsRes) ProtoMessage() {}
func (*DestroySnapshotsRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{15}
return fileDescriptor_pdu_e59763dc61674a79, []int{15}
}
func (m *DestroySnapshotsRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_DestroySnapshotsRes.Unmarshal(m, b)
@@ -833,7 +833,7 @@ func (m *ReplicationCursorReq) Reset() { *m = ReplicationCursorReq{} }
func (m *ReplicationCursorReq) String() string { return proto.CompactTextString(m) }
func (*ReplicationCursorReq) ProtoMessage() {}
func (*ReplicationCursorReq) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{16}
return fileDescriptor_pdu_e59763dc61674a79, []int{16}
}
func (m *ReplicationCursorReq) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_ReplicationCursorReq.Unmarshal(m, b)
@@ -874,7 +874,7 @@ func (m *ReplicationCursorRes) Reset() { *m = ReplicationCursorRes{} }
func (m *ReplicationCursorRes) String() string { return proto.CompactTextString(m) }
func (*ReplicationCursorRes) ProtoMessage() {}
func (*ReplicationCursorRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{17}
return fileDescriptor_pdu_e59763dc61674a79, []int{17}
}
func (m *ReplicationCursorRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_ReplicationCursorRes.Unmarshal(m, b)
@@ -1010,7 +1010,7 @@ func (m *PingReq) Reset() { *m = PingReq{} }
func (m *PingReq) String() string { return proto.CompactTextString(m) }
func (*PingReq) ProtoMessage() {}
func (*PingReq) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{18}
return fileDescriptor_pdu_e59763dc61674a79, []int{18}
}
func (m *PingReq) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_PingReq.Unmarshal(m, b)
@@ -1049,7 +1049,7 @@ func (m *PingRes) Reset() { *m = PingRes{} }
func (m *PingRes) String() string { return proto.CompactTextString(m) }
func (*PingRes) ProtoMessage() {}
func (*PingRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{19}
return fileDescriptor_pdu_e59763dc61674a79, []int{19}
}
func (m *PingRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_PingRes.Unmarshal(m, b)
@@ -1078,6 +1078,15 @@ func (m *PingRes) GetEcho() string {
type HintMostRecentCommonAncestorReq struct {
Filesystem string `protobuf:"bytes,1,opt,name=Filesystem,proto3" json:"Filesystem,omitempty"`
// A copy of the FilesystemVersion on the sending side that the replication
// algorithm identified as a shared most recent common version between sending
// and receiving side.
//
// If nil, this is an indication that the replication algorithm could not
// find a common ancestor between the two sides.
// NOTE: nilness does not mean that replication never happened - there could
// as well be a replication conflict. thus, dont' jump to conclusions too
// rapidly here.
SenderVersion *FilesystemVersion `protobuf:"bytes,2,opt,name=SenderVersion,proto3" json:"SenderVersion,omitempty"`
XXX_NoUnkeyedLiteral struct{} `json:"-"`
XXX_unrecognized []byte `json:"-"`
@@ -1088,7 +1097,7 @@ func (m *HintMostRecentCommonAncestorReq) Reset() { *m = HintMostRecentC
func (m *HintMostRecentCommonAncestorReq) String() string { return proto.CompactTextString(m) }
func (*HintMostRecentCommonAncestorReq) ProtoMessage() {}
func (*HintMostRecentCommonAncestorReq) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{20}
return fileDescriptor_pdu_e59763dc61674a79, []int{20}
}
func (m *HintMostRecentCommonAncestorReq) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_HintMostRecentCommonAncestorReq.Unmarshal(m, b)
@@ -1132,7 +1141,7 @@ func (m *HintMostRecentCommonAncestorRes) Reset() { *m = HintMostRecentC
func (m *HintMostRecentCommonAncestorRes) String() string { return proto.CompactTextString(m) }
func (*HintMostRecentCommonAncestorRes) ProtoMessage() {}
func (*HintMostRecentCommonAncestorRes) Descriptor() ([]byte, []int) {
return fileDescriptor_pdu_0f43b713cd3bf056, []int{21}
return fileDescriptor_pdu_e59763dc61674a79, []int{21}
}
func (m *HintMostRecentCommonAncestorRes) XXX_Unmarshal(b []byte) error {
return xxx_messageInfo_HintMostRecentCommonAncestorRes.Unmarshal(m, b)
@@ -1449,9 +1458,9 @@ var _Replication_serviceDesc = grpc.ServiceDesc{
Metadata: "pdu.proto",
}
func init() { proto.RegisterFile("pdu.proto", fileDescriptor_pdu_0f43b713cd3bf056) }
func init() { proto.RegisterFile("pdu.proto", fileDescriptor_pdu_e59763dc61674a79) }
var fileDescriptor_pdu_0f43b713cd3bf056 = []byte{
var fileDescriptor_pdu_e59763dc61674a79 = []byte{
// 892 bytes of a gzipped FileDescriptorProto
0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x8c, 0x56, 0xdf, 0x6f, 0xdb, 0x36,
0x10, 0x8e, 0x6c, 0x39, 0x91, 0xcf, 0xe9, 0xea, 0x5c, 0xb2, 0x42, 0x13, 0xba, 0xce, 0xe3, 0x86,
+10
View File
@@ -129,6 +129,16 @@ message PingRes {
message HintMostRecentCommonAncestorReq {
string Filesystem = 1;
// A copy of the FilesystemVersion on the sending side that the replication
// algorithm identified as a shared most recent common version between sending
// and receiving side.
//
// If nil, this is an indication that the replication algorithm could not
// find a common ancestor between the two sides.
// NOTE: nilness does not mean that replication never happened - there could
// as well be a replication conflict. thus, dont' jump to conclusions too
// rapidly here.
FilesystemVersion SenderVersion = 2;
}
message HintMostRecentCommonAncestorRes {}
+1 -1
View File
@@ -152,7 +152,7 @@ func (m *HandshakeMessage) DecodeReader(r io.Reader, maxLen int) error {
func DoHandshakeCurrentVersion(conn net.Conn, deadline time.Time) *HandshakeError {
// current protocol version is hardcoded here
return DoHandshakeVersion(conn, deadline, 2)
return DoHandshakeVersion(conn, deadline, 3)
}
const HandshakeMessageMaxLen = 16 * 4096
+16 -3
View File
@@ -1,6 +1,7 @@
package zfscmd
import (
"os/exec"
"time"
)
@@ -28,10 +29,22 @@ func waitPreLogging(c *Cmd, now time.Time) {
}
func waitPostLogging(c *Cmd, err error, now time.Time) {
var total, system, user float64
total = c.Runtime().Seconds()
if ee, ok := err.(*exec.ExitError); ok {
system = ee.ProcessState.SystemTime().Seconds()
user = ee.ProcessState.UserTime().Seconds()
} else {
system = -1
user = -1
}
log := c.log().
WithField("total_time_s", c.Runtime().Seconds()).
WithField("systemtime_s", c.cmd.ProcessState.SystemTime().Seconds()).
WithField("usertime_s", c.cmd.ProcessState.UserTime().Seconds())
WithField("total_time_s", total).
WithField("systemtime_s", system).
WithField("usertime_s", user)
if err == nil {
log.Info("command exited without error")
+29
View File
@@ -1,7 +1,9 @@
package zfscmd
import (
"bufio"
"bytes"
"context"
"io"
"os/exec"
"testing"
@@ -58,3 +60,30 @@ func TestCmdStderrBehaviorStdoutPipe(t *testing.T) {
require.True(t, ok)
require.Empty(t, ee.Stderr) // !!!!! probably not what one would expect if we only redirect stdout
}
func TestCmdProcessState(t *testing.T) {
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
cmd := exec.CommandContext(ctx, "bash", "-c", "echo running; sleep 3600")
stdout, err := cmd.StdoutPipe()
require.NoError(t, err)
err = cmd.Start()
require.NoError(t, err)
r := bufio.NewReader(stdout)
line, err := r.ReadString('\n')
require.NoError(t, err)
require.Equal(t, "running\n", line)
// we know it's running and sleeping
cancel()
err = cmd.Wait()
t.Logf("wait err %T\n%s", err, err)
require.Error(t, err)
ee, ok := err.(*exec.ExitError)
require.True(t, ok)
require.NotNil(t, ee.ProcessState)
require.Contains(t, ee.Error(), "killed")
}