"strconv"
"strings"
"sync"
+ "sync/atomic"
"time"
)
var (
maxBlockSize = 1 << 26
- concurrentWriters = 4 // max goroutines writing to Keep during sync()
- writeAheadBlocks = 1 // max background jobs flushing to Keep before blocking writes
+ concurrentWriters = 4 // max goroutines writing to Keep in background and during flush()
)
// A CollectionFileSystem is a FileSystem that can be serialized as a
// FileSystem returns a CollectionFileSystem for the collection.
func (c *Collection) FileSystem(client apiClient, kc keepClient) (CollectionFileSystem, error) {
- var modTime time.Time
- if c.ModifiedAt == nil {
+ modTime := c.ModifiedAt
+ if modTime.IsZero() {
modTime = time.Now()
- } else {
- modTime = *c.ModifiedAt
}
fs := &collectionFileSystem{
uuid: c.UUID,
fileSystem: fileSystem{
fsBackend: keepBackend{apiClient: client, keepClient: kc},
+ thr: newThrottle(concurrentWriters),
},
}
root := &dirnode{
inodes: make(map[string]inode),
},
}, nil
- } else {
- return &filenode{
- fs: fs,
- fileinfo: fileinfo{
- name: name,
- mode: perm & ^os.ModeDir,
- modTime: modTime,
- },
- }, nil
}
+ return &filenode{
+ fs: fs,
+ fileinfo: fileinfo{
+ name: name,
+ mode: perm & ^os.ModeDir,
+ modTime: modTime,
+ },
+ }, nil
+}
+
+func (fs *collectionFileSystem) Child(name string, replace func(inode) (inode, error)) (inode, error) {
+ return fs.rootnode().Child(name, replace)
+}
+
+func (fs *collectionFileSystem) FS() FileSystem {
+ return fs
+}
+
+func (fs *collectionFileSystem) FileInfo() os.FileInfo {
+ return fs.rootnode().FileInfo()
+}
+
+func (fs *collectionFileSystem) IsDir() bool {
+ return true
+}
+
+func (fs *collectionFileSystem) Lock() {
+ fs.rootnode().Lock()
+}
+
+func (fs *collectionFileSystem) Unlock() {
+ fs.rootnode().Unlock()
+}
+
+func (fs *collectionFileSystem) RLock() {
+ fs.rootnode().RLock()
+}
+
+func (fs *collectionFileSystem) RUnlock() {
+ fs.rootnode().RUnlock()
+}
+
+func (fs *collectionFileSystem) Parent() inode {
+ return fs.rootnode().Parent()
+}
+
+func (fs *collectionFileSystem) Read(_ []byte, ptr filenodePtr) (int, filenodePtr, error) {
+ return 0, ptr, ErrInvalidOperation
+}
+
+func (fs *collectionFileSystem) Write(_ []byte, ptr filenodePtr) (int, filenodePtr, error) {
+ return 0, ptr, ErrInvalidOperation
+}
+
+func (fs *collectionFileSystem) Readdir() ([]os.FileInfo, error) {
+ return fs.rootnode().Readdir()
+}
+
+func (fs *collectionFileSystem) SetParent(parent inode, name string) {
+ fs.rootnode().SetParent(parent, name)
+}
+
+func (fs *collectionFileSystem) Truncate(int64) error {
+ return ErrInvalidOperation
}
func (fs *collectionFileSystem) Sync() error {
return nil
}
+func (fs *collectionFileSystem) Flush(path string, shortBlocks bool) error {
+ node, err := rlookup(fs.fileSystem.root, path)
+ if err != nil {
+ return err
+ }
+ dn, ok := node.(*dirnode)
+ if !ok {
+ return ErrNotADirectory
+ }
+ dn.Lock()
+ defer dn.Unlock()
+ names := dn.sortedNames()
+ if path != "" {
+ // Caller only wants to flush the specified dir,
+ // non-recursively. Drop subdirs from the list of
+ // names.
+ var filenames []string
+ for _, name := range names {
+ if _, ok := dn.inodes[name].(*filenode); ok {
+ filenames = append(filenames, name)
+ }
+ }
+ names = filenames
+ }
+ for _, name := range names {
+ child := dn.inodes[name]
+ child.Lock()
+ defer child.Unlock()
+ }
+ return dn.flush(context.TODO(), names, flushOpts{sync: false, shortBlocks: shortBlocks})
+}
+
+func (fs *collectionFileSystem) MemorySize() int64 {
+ fs.fileSystem.root.Lock()
+ defer fs.fileSystem.root.Unlock()
+ return fs.fileSystem.root.(*dirnode).MemorySize()
+}
+
func (fs *collectionFileSystem) MarshalManifest(prefix string) (string, error) {
fs.fileSystem.root.Lock()
defer fs.fileSystem.root.Unlock()
- return fs.fileSystem.root.(*dirnode).marshalManifest(context.TODO(), prefix, newThrottle(concurrentWriters))
+ return fs.fileSystem.root.(*dirnode).marshalManifest(context.TODO(), prefix)
}
func (fs *collectionFileSystem) Size() int64 {
memsize int64 // bytes in memSegments
sync.RWMutex
nullnode
- throttle *throttle
}
// caller must have lock
seg.Truncate(len(cando))
fn.memsize += int64(len(cando))
fn.segments[cur] = seg
- cur++
- prev++
}
}
// Write some data out to disk to reduce memory use. Caller must have
// write lock.
func (fn *filenode) pruneMemSegments() {
- // TODO: share code with (*dirnode)sync()
+ // TODO: share code with (*dirnode)flush()
// TODO: pack/flush small blocks too, when fragmented
- if fn.throttle == nil {
- // TODO: share a throttle with filesystem
- fn.throttle = newThrottle(writeAheadBlocks)
- }
for idx, seg := range fn.segments {
seg, ok := seg.(*memSegment)
if !ok || seg.Len() < maxBlockSize || seg.flushing != nil {
// progress, block here until one finishes, rather
// than pile up an unlimited number of buffered writes
// and network flush operations.
- fn.throttle.Acquire()
+ fn.fs.throttle().Acquire()
go func() {
defer close(done)
locator, _, err := fn.FS().PutB(buf)
- fn.throttle.Release()
+ fn.fs.throttle().Release()
fn.Lock()
defer fn.Unlock()
- if curbuf := seg.buf[:1]; &curbuf[0] != &buf[0] {
+ if seg.flushing != done {
// A new seg.buf has been allocated.
return
}
- seg.flushing = nil
if err != nil {
// TODO: stall (or return errors from)
// subsequent writes until flushing
}
}
-// Block until all pending pruneMemSegments work is finished. Caller
-// must NOT have lock.
+// Block until all pending pruneMemSegments/flush work is
+// finished. Caller must NOT have lock.
func (fn *filenode) waitPrune() {
var pending []<-chan struct{}
fn.Lock()
if err != nil {
return nil, err
}
+ coll.UUID = dn.fs.uuid
data, err := json.Marshal(&coll)
if err == nil {
data = append(data, '\n')
// storedSegments that reference the relevant portions of the new
// block.
//
+// bufsize is the total data size in refs. It is used to preallocate
+// the correct amount of memory when len(refs)>1.
+//
+// If sync is false, commitBlock returns right away, after starting a
+// goroutine to do the writes, reacquire the filenodes' locks, and
+// swap out the *memSegments. Some filenodes' segments might get
+// modified/rearranged in the meantime, in which case commitBlock
+// won't replace them.
+//
// Caller must have write lock.
-func (dn *dirnode) commitBlock(ctx context.Context, throttle *throttle, refs []fnSegmentRef) error {
+func (dn *dirnode) commitBlock(ctx context.Context, refs []fnSegmentRef, bufsize int, sync bool) error {
if len(refs) == 0 {
return nil
}
- throttle.Acquire()
- defer throttle.Release()
if err := ctx.Err(); err != nil {
return err
}
- block := make([]byte, 0, maxBlockSize)
+ done := make(chan struct{})
+ var block []byte
+ segs := make([]*memSegment, 0, len(refs))
+ offsets := make([]int, 0, len(refs)) // location of segment's data within block
for _, ref := range refs {
- block = append(block, ref.fn.segments[ref.idx].(*memSegment).buf...)
- }
- locator, _, err := dn.fs.PutB(block)
- if err != nil {
- return err
+ seg := ref.fn.segments[ref.idx].(*memSegment)
+ if !sync && seg.flushingUnfinished() {
+ // Let the other flushing goroutine finish. If
+ // it fails, we'll try again next time.
+ close(done)
+ return nil
+ }
+ // In sync mode, we proceed regardless of
+ // whether another flush is in progress: It
+ // can't finish before we do, because we hold
+ // fn's lock until we finish our own writes.
+ seg.flushing = done
+ offsets = append(offsets, len(block))
+ if len(refs) == 1 {
+ block = seg.buf
+ } else if block == nil {
+ block = append(make([]byte, 0, bufsize), seg.buf...)
+ } else {
+ block = append(block, seg.buf...)
+ }
+ segs = append(segs, seg)
}
- off := 0
- for _, ref := range refs {
- data := ref.fn.segments[ref.idx].(*memSegment).buf
- ref.fn.segments[ref.idx] = storedSegment{
- kc: dn.fs,
- locator: locator,
- size: len(block),
- offset: off,
- length: len(data),
+ blocksize := len(block)
+ dn.fs.throttle().Acquire()
+ errs := make(chan error, 1)
+ go func() {
+ defer close(done)
+ defer close(errs)
+ locator, _, err := dn.fs.PutB(block)
+ dn.fs.throttle().Release()
+ if err != nil {
+ errs <- err
+ return
}
- off += len(data)
- ref.fn.memsize -= int64(len(data))
+ for idx, ref := range refs {
+ if !sync {
+ ref.fn.Lock()
+ // In async mode, fn's lock was
+ // released while we were waiting for
+ // PutB(); lots of things might have
+ // changed.
+ if len(ref.fn.segments) <= ref.idx {
+ // file segments have
+ // rearranged or changed in
+ // some way
+ ref.fn.Unlock()
+ continue
+ } else if seg, ok := ref.fn.segments[ref.idx].(*memSegment); !ok || seg != segs[idx] {
+ // segment has been replaced
+ ref.fn.Unlock()
+ continue
+ } else if seg.flushing != done {
+ // seg.buf has been replaced
+ ref.fn.Unlock()
+ continue
+ }
+ }
+ data := ref.fn.segments[ref.idx].(*memSegment).buf
+ ref.fn.segments[ref.idx] = storedSegment{
+ kc: dn.fs,
+ locator: locator,
+ size: blocksize,
+ offset: offsets[idx],
+ length: len(data),
+ }
+ // atomic is needed here despite caller having
+ // lock: caller might be running concurrent
+ // commitBlock() goroutines using the same
+ // lock, writing different segments from the
+ // same file.
+ atomic.AddInt64(&ref.fn.memsize, -int64(len(data)))
+ if !sync {
+ ref.fn.Unlock()
+ }
+ }
+ }()
+ if sync {
+ return <-errs
}
return nil
}
-// sync flushes in-memory data and remote block references (for the
+type flushOpts struct {
+ sync bool
+ shortBlocks bool
+}
+
+// flush in-memory data and remote-cluster block references (for the
// children with the given names, which must be children of dn) to
-// local persistent storage. Caller must have write lock on dn and the
-// named children.
-func (dn *dirnode) sync(ctx context.Context, throttle *throttle, names []string) error {
+// local-cluster persistent storage.
+//
+// Caller must have write lock on dn and the named children.
+//
+// If any children are dirs, they will be flushed recursively.
+func (dn *dirnode) flush(ctx context.Context, names []string, opts flushOpts) error {
cg := newContextGroup(ctx)
defer cg.Cancel()
- goCommit := func(refs []fnSegmentRef) {
+ goCommit := func(refs []fnSegmentRef, bufsize int) {
cg.Go(func() error {
- return dn.commitBlock(cg.Context(), throttle, refs)
+ return dn.commitBlock(cg.Context(), refs, bufsize, opts.sync)
})
}
var pendingLen int = 0
localLocator := map[string]string{}
for _, name := range names {
- fn, ok := dn.inodes[name].(*filenode)
- if !ok {
- continue
- }
- for idx, seg := range fn.segments {
- switch seg := seg.(type) {
- case storedSegment:
- loc, ok := localLocator[seg.locator]
- if !ok {
- var err error
- loc, err = dn.fs.LocalLocator(seg.locator)
- if err != nil {
- return err
+ switch node := dn.inodes[name].(type) {
+ case *dirnode:
+ grandchildNames := node.sortedNames()
+ for _, grandchildName := range grandchildNames {
+ grandchild := node.inodes[grandchildName]
+ grandchild.Lock()
+ defer grandchild.Unlock()
+ }
+ cg.Go(func() error { return node.flush(cg.Context(), grandchildNames, opts) })
+ case *filenode:
+ for idx, seg := range node.segments {
+ switch seg := seg.(type) {
+ case storedSegment:
+ loc, ok := localLocator[seg.locator]
+ if !ok {
+ var err error
+ loc, err = dn.fs.LocalLocator(seg.locator)
+ if err != nil {
+ return err
+ }
+ localLocator[seg.locator] = loc
}
- localLocator[seg.locator] = loc
- }
- seg.locator = loc
- fn.segments[idx] = seg
- case *memSegment:
- if seg.Len() > maxBlockSize/2 {
- goCommit([]fnSegmentRef{{fn, idx}})
- continue
- }
- if pendingLen+seg.Len() > maxBlockSize {
- goCommit(pending)
- pending = nil
- pendingLen = 0
+ seg.locator = loc
+ node.segments[idx] = seg
+ case *memSegment:
+ if seg.Len() > maxBlockSize/2 {
+ goCommit([]fnSegmentRef{{node, idx}}, seg.Len())
+ continue
+ }
+ if pendingLen+seg.Len() > maxBlockSize {
+ goCommit(pending, pendingLen)
+ pending = nil
+ pendingLen = 0
+ }
+ pending = append(pending, fnSegmentRef{node, idx})
+ pendingLen += seg.Len()
+ default:
+ panic(fmt.Sprintf("can't sync segment type %T", seg))
}
- pending = append(pending, fnSegmentRef{fn, idx})
- pendingLen += seg.Len()
- default:
- panic(fmt.Sprintf("can't sync segment type %T", seg))
}
}
}
- goCommit(pending)
+ if opts.shortBlocks {
+ goCommit(pending, pendingLen)
+ }
return cg.Wait()
}
// caller must have write lock.
-func (dn *dirnode) marshalManifest(ctx context.Context, prefix string, throttle *throttle) (string, error) {
+func (dn *dirnode) MemorySize() (size int64) {
+ for _, name := range dn.sortedNames() {
+ node := dn.inodes[name]
+ node.Lock()
+ defer node.Unlock()
+ switch node := node.(type) {
+ case *dirnode:
+ size += node.MemorySize()
+ case *filenode:
+ for _, seg := range node.segments {
+ switch seg := seg.(type) {
+ case *memSegment:
+ size += int64(seg.Len())
+ }
+ }
+ }
+ }
+ return
+}
+
+// caller must have write lock.
+func (dn *dirnode) sortedNames() []string {
+ names := make([]string, 0, len(dn.inodes))
+ for name := range dn.inodes {
+ names = append(names, name)
+ }
+ sort.Strings(names)
+ return names
+}
+
+// caller must have write lock.
+func (dn *dirnode) marshalManifest(ctx context.Context, prefix string) (string, error) {
cg := newContextGroup(ctx)
defer cg.Cancel()
return manifestEscape(prefix) + " d41d8cd98f00b204e9800998ecf8427e+0 0:0:\\056\n", nil
}
- names := make([]string, 0, len(dn.inodes))
- for name := range dn.inodes {
- names = append(names, name)
- }
- sort.Strings(names)
+ names := dn.sortedNames()
// Wait for children to finish any pending write operations
// before locking them.
for i, name := range dirnames {
i, name := i, name
cg.Go(func() error {
- txt, err := dn.inodes[name].(*dirnode).marshalManifest(cg.Context(), prefix+"/"+name, throttle)
+ txt, err := dn.inodes[name].(*dirnode).marshalManifest(cg.Context(), prefix+"/"+name)
subdirs[i] = txt
return err
})
var fileparts []filepart
var blocks []string
- if err := dn.sync(cg.Context(), throttle, names); err != nil {
+ if err := dn.flush(cg.Context(), filenames, flushOpts{sync: true, shortBlocks: true}); err != nil {
return err
}
for _, name := range filenames {
default:
// This can't happen: we
// haven't unlocked since
- // calling sync().
+ // calling flush(sync=true).
panic(fmt.Sprintf("can't marshal segment type %T", seg))
}
}
// situation might be rare anyway)
segIdx, pos = 0, 0
}
- for next := int64(0); segIdx < len(segments); segIdx++ {
+ for ; segIdx < len(segments); segIdx++ {
seg := segments[segIdx]
- next = pos + int64(seg.Len())
+ next := pos + int64(seg.Len())
if next <= offset || seg.Len() == 0 {
pos = next
continue
node = node.Parent()
continue
}
+ modtime := node.Parent().FileInfo().ModTime()
+ node.Lock()
+ locked := node
node, err = node.Child(name, func(child inode) (inode, error) {
if child == nil {
- child, err := node.FS().newNode(name, 0755|os.ModeDir, node.Parent().FileInfo().ModTime())
+ child, err := node.FS().newNode(name, 0755|os.ModeDir, modtime)
if err != nil {
return nil, err
}
return child, nil
}
})
+ locked.Unlock()
if err != nil {
return
}
err = fmt.Errorf("invalid file part %q in path %q", basename, path)
return
}
+ modtime := node.FileInfo().ModTime()
+ node.Lock()
+ defer node.Unlock()
_, err = node.Child(basename, func(child inode) (inode, error) {
switch child := child.(type) {
case nil:
- child, err = node.FS().newNode(basename, 0755, node.FileInfo().ModTime())
+ child, err = node.FS().newNode(basename, 0755, modtime)
if err != nil {
return nil, err
}
type memSegment struct {
buf []byte
- // If flushing is not nil, then a) buf is being shared by a
- // pruneMemSegments goroutine, and must be copied on write;
- // and b) the flushing channel will close when the goroutine
- // finishes, whether it succeeds or not.
+ // If flushing is not nil and not ready/closed, then a) buf is
+ // being shared by a pruneMemSegments goroutine, and must be
+ // copied on write; and b) the flushing channel will close
+ // when the goroutine finishes, whether it succeeds or not.
flushing <-chan struct{}
}
+func (me *memSegment) flushingUnfinished() bool {
+ if me.flushing == nil {
+ return false
+ }
+ select {
+ case <-me.flushing:
+ me.flushing = nil
+ return false
+ default:
+ return true
+ }
+}
+
func (me *memSegment) Len() int {
return len(me.buf)
}
projects / arvados.git / blobdiff