func (ds *DiskStorage) StatBlobs(dest chan<- blob.SizedRef, blobs []blob.Ref) error {
if len(blobs) == 0 {
return nil
}
statSend := func(ref blob.Ref) error {
fi, err := os.Stat(ds.blobPath(ds.partition, ref))
switch {
case err == nil && fi.Mode().IsRegular():
dest <- blob.SizedRef{Ref: ref, Size: fi.Size()}
return nil
case err != nil && !os.IsNotExist(err):
return err
}
return nil
}
if len(blobs) == 1 {
return statSend(blobs[0])
}
errc := make(chan error, len(blobs))
gt := gate.New(maxParallelStats)
for _, ref := range blobs {
gt.Start()
go func(ref blob.Ref) {
defer gt.Done()
errc <- statSend(ref)
}(ref)
}
for _ = range blobs {
if err := <-errc; err != nil {
return err
}
}
return nil
}
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package s3
import (
"fmt"
"os"
"camlistore.org/pkg/blob"
"camlistore.org/pkg/gate"
)
var statGate = gate.New(20) // arbitrary
func (sto *s3Storage) StatBlobs(dest chan<- blob.SizedRef, blobs []blob.Ref) error {
errc := make(chan error, len(blobs))
for _, br := range blobs {
statGate.Start()
go func(br blob.Ref) {
defer statGate.Done()
size, err := sto.s3Client.Stat(br.String(), sto.bucket)
switch err {
case nil:
dest <- blob.SizedRef{Ref: br, Size: size}
errc <- nil
case os.ErrNotExist:
errc <- nil
default:
func writeFileChunks(bs blobserver.StatReceiver, file *Builder, r io.Reader) (n int64, spans []span, outerr error) {
src := ¬eEOFReader{r: r}
bufr := bufio.NewReaderSize(src, bufioReaderSize)
spans = []span{} // the tree of spans, cut on interesting rollsum boundaries
rs := rollsum.New()
var last int64
var buf bytes.Buffer
blobSize := 0 // of the next blob being built, should be same as buf.Len()
const chunksInFlight = 32 // at ~64 KB chunks, this is ~2MB memory per file
gatec := gate.New(chunksInFlight)
firsterrc := make(chan error, 1)
// uploadLastSpan runs in the same goroutine as the loop below and is responsible for
// starting uploading the contents of the buf. It returns false if there's been
// an error and the loop below should be stopped.
uploadLastSpan := func() bool {
chunk := buf.String()
buf.Reset()
br := blob.SHA1FromString(chunk)
spans[len(spans)-1].br = br
select {
case outerr = <-firsterrc:
return false
default:
// No error seen so far, continue.
}
gatec.Start()
go func() {
defer gatec.Done()
if _, err := uploadString(bs, br, chunk); err != nil {
select {
case firsterrc <- err:
default:
}
}
}()
return true
}
for {
c, err := bufr.ReadByte()
if err == io.EOF {
if n != last {
spans = append(spans, span{from: last, to: n})
if !uploadLastSpan() {
return
}
}
break
}
if err != nil {
return 0, nil, err
}
buf.WriteByte(c)
n++
blobSize++
rs.Roll(c)
var bits int
onRollSplit := rs.OnSplit()
switch {
case blobSize == maxBlobSize:
bits = 20 // arbitrary node weight; 1<<20 == 1MB
case src.sawEOF:
// Don't split. End is coming soon enough.
continue
case onRollSplit && n > firstChunkSize && blobSize > tooSmallThreshold:
bits = rs.Bits()
case n == firstChunkSize:
bits = 18 // 1 << 18 == 256KB
default:
// Don't split.
continue
}
blobSize = 0
// Take any spans from the end of the spans slice that
// have a smaller 'bits' score and make them children
// of this node.
var children []span
childrenFrom := len(spans)
for childrenFrom > 0 && spans[childrenFrom-1].bits < bits {
childrenFrom--
}
if nCopy := len(spans) - childrenFrom; nCopy > 0 {
children = make([]span, nCopy)
copy(children, spans[childrenFrom:])
spans = spans[:childrenFrom]
}
spans = append(spans, span{from: last, to: n, bits: bits, children: children})
last = n
if !uploadLastSpan() {
return
}
}
// Loop was already hit earlier.
if outerr != nil {
return 0, nil, outerr
}
// Wait for all uploads to finish, one way or another, and then
// see if any generated errors.
// Once this loop is done, we own all the tokens in gatec, so nobody
// else can have one outstanding.
for i := 0; i < chunksInFlight; i++ {
gatec.Start()
}
select {
case err := <-firsterrc:
return 0, nil, err
default:
}
return n, spans, nil
}
