diff --git a/vendor/github.com/pierrec/lz4/README.md b/vendor/github.com/pierrec/lz4/README.md
index 00899fb..4ee388e 100644
--- a/vendor/github.com/pierrec/lz4/README.md
+++ b/vendor/github.com/pierrec/lz4/README.md
@@ -83,23 +83,8 @@
 
 ## Contributors
 
-Thanks to all contributors so far:
+Thanks to all [contributors](https://github.com/pierrec/lz4/graphs/contributors)  so far!
 
-- [@klauspost](https://github.com/klauspost)
-- [@heidawei](https://github.com/heidawei)
-- [@x4m](https://github.com/x4m)
-- [@Zariel](https://github.com/Zariel)
-- [@edwingeng](https://github.com/edwingeng)
-- [@danielmoy-google](https://github.com/danielmoy-google)
-- [@honda-tatsuya](https://github.com/honda-tatsuya)
-- [@h8liu](https://github.com/h8liu)
-- [@sbinet](https://github.com/sbinet)
-- [@fingon](https://github.com/fingon)
-- [@emfree](https://github.com/emfree)
-- [@lhemala](https://github.com/lhemala)
-- [@connor4312](https://github.com/connor4312)
-- [@oov](https://github.com/oov)
-- [@arya](https://github.com/arya)
-- [@ikkeps](https://github.com/ikkeps)
+Special thanks to [@Zariel](https://github.com/Zariel) for his asm implementation of the decoder.
 
-Special thanks to [@Zariel](https://github.com/Zariel) for his asm implementation of the decoder
+Special thanks to [@klauspost](https://github.com/klauspost) for his work on optimizing the code.
diff --git a/vendor/github.com/pierrec/lz4/block.go b/vendor/github.com/pierrec/lz4/block.go
index 5755cda..b589af4 100644
--- a/vendor/github.com/pierrec/lz4/block.go
+++ b/vendor/github.com/pierrec/lz4/block.go
@@ -40,7 +40,10 @@
 // The size of the compressed data is returned. If it is 0 and no error, then the data is incompressible.
 //
 // An error is returned if the destination buffer is too small.
-func CompressBlock(src, dst []byte, hashTable []int) (di int, err error) {
+func CompressBlock(src, dst []byte, hashTable []int) (_ int, err error) {
+	if len(hashTable) < htSize {
+		return 0, fmt.Errorf("hash table too small, should be at least %d in size", htSize)
+	}
 	defer recoverBlock(&err)
 
 	// adaptSkipLog sets how quickly the compressor begins skipping blocks when data is incompressible.
@@ -51,16 +54,13 @@
 	if sn <= 0 || dn == 0 {
 		return 0, nil
 	}
-	if len(hashTable) < htSize {
-		return 0, fmt.Errorf("hash table too small, should be at least %d in size", htSize)
-	}
 	// Prove to the compiler the table has at least htSize elements.
 	// The compiler can see that "uint32() >> hashShift" cannot be out of bounds.
 	hashTable = hashTable[:htSize]
 
 	// si: Current position of the search.
 	// anchor: Position of the current literals.
-	var si, anchor int
+	var si, di, anchor int
 
 	// Fast scan strategy: the hash table only stores the last 4 bytes sequences.
 	for si < sn {
@@ -124,7 +124,7 @@
 		si, mLen = si+mLen, si+minMatch
 
 		// Find the longest match by looking by batches of 8 bytes.
-		for si < sn {
+		for si+8 < sn {
 			x := binary.LittleEndian.Uint64(src[si:]) ^ binary.LittleEndian.Uint64(src[si-offset:])
 			if x == 0 {
 				si += 8
@@ -227,7 +227,7 @@
 // The size of the compressed data is returned. If it is 0 and no error, then the data is not compressible.
 //
 // An error is returned if the destination buffer is too small.
-func CompressBlockHC(src, dst []byte, depth int) (di int, err error) {
+func CompressBlockHC(src, dst []byte, depth int) (_ int, err error) {
 	defer recoverBlock(&err)
 
 	// adaptSkipLog sets how quickly the compressor begins skipping blocks when data is incompressible.
@@ -239,7 +239,7 @@
 	if sn <= 0 || dn == 0 {
 		return 0, nil
 	}
-	var si int
+	var si, di int
 
 	// hashTable: stores the last position found for a given hash
 	// chainTable: stores previous positions for a given hash
diff --git a/vendor/github.com/pierrec/lz4/decode_other.go b/vendor/github.com/pierrec/lz4/decode_other.go
index 002519f..919888e 100644
--- a/vendor/github.com/pierrec/lz4/decode_other.go
+++ b/vendor/github.com/pierrec/lz4/decode_other.go
@@ -19,7 +19,7 @@
 		// Literals.
 		if lLen := b >> 4; lLen > 0 {
 			switch {
-			case lLen < 0xF && di+18 < len(dst) && si+16 < len(src):
+			case lLen < 0xF && si+16 < len(src):
 				// Shortcut 1
 				// if we have enough room in src and dst, and the literals length
 				// is small enough (0..14) then copy all 16 bytes, even if not all
@@ -34,7 +34,13 @@
 					mLen += 4
 					if offset := int(src[si]) | int(src[si+1])<<8; mLen <= offset {
 						i := di - offset
-						copy(dst[di:], dst[i:i+18])
+						end := i + 18
+						if end > len(dst) {
+							// The remaining buffer may not hold 18 bytes.
+							// See https://github.com/pierrec/lz4/issues/51.
+							end = len(dst)
+						}
+						copy(dst[di:], dst[i:end])
 						si += 2
 						di += mLen
 						continue
diff --git a/vendor/github.com/pierrec/lz4/errors.go b/vendor/github.com/pierrec/lz4/errors.go
index 3e27894..1c45d18 100644
--- a/vendor/github.com/pierrec/lz4/errors.go
+++ b/vendor/github.com/pierrec/lz4/errors.go
@@ -15,6 +15,8 @@
 	ErrInvalid = errors.New("lz4: bad magic number")
 	// ErrBlockDependency is returned when attempting to decompress an archive created with block dependency.
 	ErrBlockDependency = errors.New("lz4: block dependency not supported")
+	// ErrUnsupportedSeek is returned when attempting to Seek any way but forward from the current position.
+	ErrUnsupportedSeek = errors.New("lz4: can only seek forward from io.SeekCurrent")
 )
 
 func recoverBlock(e *error) {
diff --git a/vendor/github.com/pierrec/lz4/lz4.go b/vendor/github.com/pierrec/lz4/lz4.go
index cdbf961..29864d8 100644
--- a/vendor/github.com/pierrec/lz4/lz4.go
+++ b/vendor/github.com/pierrec/lz4/lz4.go
@@ -10,6 +10,10 @@
 //
 package lz4
 
+import "math/bits"
+
+import "sync"
+
 const (
 	// Extension is the LZ4 frame file name extension
 	Extension = ".lz4"
@@ -34,22 +38,61 @@
 	hashLog = 16
 	htSize  = 1 << hashLog
 
-	mfLimit = 8 + minMatch // The last match cannot start within the last 12 bytes.
+	mfLimit = 10 + minMatch // The last match cannot start within the last 14 bytes.
 )
 
 // map the block max size id with its value in bytes: 64Kb, 256Kb, 1Mb and 4Mb.
 const (
-	blockSize64K  = 64 << 10
-	blockSize256K = 256 << 10
-	blockSize1M   = 1 << 20
-	blockSize4M   = 4 << 20
+	blockSize64K = 1 << (16 + 2*iota)
+	blockSize256K
+	blockSize1M
+	blockSize4M
 )
 
 var (
-	bsMapID    = map[byte]int{4: blockSize64K, 5: blockSize256K, 6: blockSize1M, 7: blockSize4M}
-	bsMapValue = map[int]byte{blockSize64K: 4, blockSize256K: 5, blockSize1M: 6, blockSize4M: 7}
+	// Keep a pool of buffers for each valid block sizes.
+	bsMapValue = [...]*sync.Pool{
+		newBufferPool(2 * blockSize64K),
+		newBufferPool(2 * blockSize256K),
+		newBufferPool(2 * blockSize1M),
+		newBufferPool(2 * blockSize4M),
+	}
 )
 
+// newBufferPool returns a pool for buffers of the given size.
+func newBufferPool(size int) *sync.Pool {
+	return &sync.Pool{
+		New: func() interface{} {
+			return make([]byte, size)
+		},
+	}
+}
+
+// getBuffer returns a buffer to its pool.
+func getBuffer(size int) []byte {
+	idx := blockSizeValueToIndex(size) - 4
+	return bsMapValue[idx].Get().([]byte)
+}
+
+// putBuffer returns a buffer to its pool.
+func putBuffer(size int, buf []byte) {
+	if cap(buf) > 0 {
+		idx := blockSizeValueToIndex(size) - 4
+		bsMapValue[idx].Put(buf[:cap(buf)])
+	}
+}
+func blockSizeIndexToValue(i byte) int {
+	return 1 << (16 + 2*uint(i))
+}
+func isValidBlockSize(size int) bool {
+	const blockSizeMask = blockSize64K | blockSize256K | blockSize1M | blockSize4M
+
+	return size&blockSizeMask > 0 && bits.OnesCount(uint(size)) == 1
+}
+func blockSizeValueToIndex(size int) byte {
+	return 4 + byte(bits.TrailingZeros(uint(size)>>16)/2)
+}
+
 // Header describes the various flags that can be set on a Writer or obtained from a Reader.
 // The default values match those of the LZ4 frame format definition
 // (http://fastcompression.blogspot.com/2013/04/lz4-streaming-format-final.html).
@@ -64,3 +107,7 @@
 	CompressionLevel int    // Compression level (higher is better, use 0 for fastest compression).
 	done             bool   // Header processed flag (Read or Write and checked).
 }
+
+func (h *Header) Reset() {
+	h.done = false
+}
diff --git a/vendor/github.com/pierrec/lz4/reader.go b/vendor/github.com/pierrec/lz4/reader.go
index 90e8efe..87dd72b 100644
--- a/vendor/github.com/pierrec/lz4/reader.go
+++ b/vendor/github.com/pierrec/lz4/reader.go
@@ -25,6 +25,8 @@
 	data     []byte        // Uncompressed data.
 	idx      int           // Index of unread bytes into data.
 	checksum xxh32.XXHZero // Frame hash.
+	skip     int64         // Bytes to skip before next read.
+	dpos     int64         // Position in dest
 }
 
 // NewReader returns a new LZ4 frame decoder.
@@ -86,10 +88,10 @@
 	z.NoChecksum = b>>2&1 == 0
 
 	bmsID := buf[1] >> 4 & 0x7
-	bSize, ok := bsMapID[bmsID]
-	if !ok {
+	if bmsID < 4 || bmsID > 7 {
 		return fmt.Errorf("lz4: invalid block max size ID: %d", bmsID)
 	}
+	bSize := blockSizeIndexToValue(bmsID - 4)
 	z.BlockMaxSize = bSize
 
 	// Allocate the compressed/uncompressed buffers.
@@ -275,8 +277,20 @@
 		z.idx = 0
 	}
 
+	if z.skip > int64(len(z.data[z.idx:])) {
+		z.skip -= int64(len(z.data[z.idx:]))
+		z.dpos += int64(len(z.data[z.idx:]))
+		z.idx = len(z.data)
+		return 0, nil
+	}
+
+	z.idx += int(z.skip)
+	z.dpos += z.skip
+	z.skip = 0
+
 	n := copy(buf, z.data[z.idx:])
 	z.idx += n
+	z.dpos += int64(n)
 	if debugFlag {
 		debug("copied %d bytes to input", n)
 	}
@@ -284,6 +298,20 @@
 	return n, nil
 }
 
+// Seek implements io.Seeker, but supports seeking forward from the current
+// position only. Any other seek will return an error. Allows skipping output
+// bytes which aren't needed, which in some scenarios is faster than reading
+// and discarding them.
+// Note this may cause future calls to Read() to read 0 bytes if all of the
+// data they would have returned is skipped.
+func (z *Reader) Seek(offset int64, whence int) (int64, error) {
+	if offset < 0 || whence != io.SeekCurrent {
+		return z.dpos + z.skip, ErrUnsupportedSeek
+	}
+	z.skip += offset
+	return z.dpos + z.skip, nil
+}
+
 // Reset discards the Reader's state and makes it equivalent to the
 // result of its original state from NewReader, but reading from r instead.
 // This permits reusing a Reader rather than allocating a new one.
diff --git a/vendor/github.com/pierrec/lz4/writer.go b/vendor/github.com/pierrec/lz4/writer.go
index 804a68c..324f138 100644
--- a/vendor/github.com/pierrec/lz4/writer.go
+++ b/vendor/github.com/pierrec/lz4/writer.go
@@ -3,11 +3,18 @@
 import (
 	"encoding/binary"
 	"fmt"
-	"io"
-
 	"github.com/pierrec/lz4/internal/xxh32"
+	"io"
+	"runtime"
 )
 
+// zResult contains the results of compressing a block.
+type zResult struct {
+	size     uint32 // Block header
+	data     []byte // Compressed data
+	checksum uint32 // Data checksum
+}
+
 // Writer implements the LZ4 frame encoder.
 type Writer struct {
 	Header
@@ -18,10 +25,13 @@
 	buf       [19]byte      // magic number(4) + header(flags(2)+[Size(8)+DictID(4)]+checksum(1)) does not exceed 19 bytes
 	dst       io.Writer     // Destination.
 	checksum  xxh32.XXHZero // Frame checksum.
-	zdata     []byte        // Compressed data.
-	data      []byte        // Data to be compressed.
+	data      []byte        // Data to be compressed + buffer for compressed data.
 	idx       int           // Index into data.
 	hashtable [winSize]int  // Hash table used in CompressBlock().
+
+	// For concurrency.
+	c   chan chan zResult // Channel for block compression goroutines and writer goroutine.
+	err error             // Any error encountered while writing to the underlying destination.
 }
 
 // NewWriter returns a new LZ4 frame encoder.
@@ -29,28 +39,92 @@
 // The supplied Header is checked at the first Write.
 // It is ok to change it before the first Write but then not until a Reset() is performed.
 func NewWriter(dst io.Writer) *Writer {
-	return &Writer{dst: dst}
+	z := new(Writer)
+	z.Reset(dst)
+	return z
+}
+
+// WithConcurrency sets the number of concurrent go routines used for compression.
+// A negative value sets the concurrency to GOMAXPROCS.
+func (z *Writer) WithConcurrency(n int) *Writer {
+	switch {
+	case n == 0 || n == 1:
+		z.c = nil
+		return z
+	case n < 0:
+		n = runtime.GOMAXPROCS(0)
+	}
+	z.c = make(chan chan zResult, n)
+	// Writer goroutine managing concurrent block compression goroutines.
+	go func() {
+		// Process next block compression item.
+		for c := range z.c {
+			// Read the next compressed block result.
+			// Waiting here ensures that the blocks are output in the order they were sent.
+			// The incoming channel is always closed as it indicates to the caller that
+			// the block has been processed.
+			res := <-c
+			n := len(res.data)
+			if n == 0 {
+				// Notify the block compression routine that we are done with its result.
+				// This is used when a sentinel block is sent to terminate the compression.
+				close(c)
+				return
+			}
+			// Write the block.
+			if err := z.writeUint32(res.size); err != nil && z.err == nil {
+				z.err = err
+			}
+			if _, err := z.dst.Write(res.data); err != nil && z.err == nil {
+				z.err = err
+			}
+			if z.BlockChecksum {
+				if err := z.writeUint32(res.checksum); err != nil && z.err == nil {
+					z.err = err
+				}
+			}
+			if isCompressed := res.size&compressedBlockFlag == 0; isCompressed {
+				// It is now safe to release the buffer as no longer in use by any goroutine.
+				putBuffer(cap(res.data), res.data)
+			}
+			if h := z.OnBlockDone; h != nil {
+				h(n)
+			}
+			close(c)
+		}
+	}()
+	return z
+}
+
+// newBuffers instantiates new buffers which size matches the one in Header.
+// The returned buffers are for decompression and compression respectively.
+func (z *Writer) newBuffers() {
+	bSize := z.Header.BlockMaxSize
+	buf := getBuffer(bSize)
+	z.data = buf[:bSize] // Uncompressed buffer is the first half.
+}
+
+// freeBuffers puts the writer's buffers back to the pool.
+func (z *Writer) freeBuffers() {
+	// Put the buffer back into the pool, if any.
+	putBuffer(z.Header.BlockMaxSize, z.data)
+	z.data = nil
 }
 
 // writeHeader builds and writes the header (magic+header) to the underlying io.Writer.
 func (z *Writer) writeHeader() error {
 	// Default to 4Mb if BlockMaxSize is not set.
 	if z.Header.BlockMaxSize == 0 {
-		z.Header.BlockMaxSize = bsMapID[7]
+		z.Header.BlockMaxSize = blockSize4M
 	}
 	// The only option that needs to be validated.
 	bSize := z.Header.BlockMaxSize
-	bSizeID, ok := bsMapValue[bSize]
-	if !ok {
+	if !isValidBlockSize(z.Header.BlockMaxSize) {
 		return fmt.Errorf("lz4: invalid block max size: %d", bSize)
 	}
 	// Allocate the compressed/uncompressed buffers.
 	// The compressed buffer cannot exceed the uncompressed one.
-	if n := 2 * bSize; cap(z.zdata) < n {
-		z.zdata = make([]byte, n, n)
-	}
-	z.data = z.zdata[:bSize]
-	z.zdata = z.zdata[:cap(z.zdata)][bSize:]
+	z.newBuffers()
 	z.idx = 0
 
 	// Size is optional.
@@ -70,7 +144,7 @@
 		flg |= 1 << 2
 	}
 	buf[4] = flg
-	buf[5] = bSizeID << 4
+	buf[5] = blockSizeValueToIndex(z.Header.BlockMaxSize) << 4
 
 	// Current buffer size: magic(4) + flags(1) + block max size (1).
 	n := 6
@@ -150,28 +224,34 @@
 // compressBlock compresses a block.
 func (z *Writer) compressBlock(data []byte) error {
 	if !z.NoChecksum {
-		z.checksum.Write(data)
+		_, _ = z.checksum.Write(data)
 	}
 
+	if z.c != nil {
+		c := make(chan zResult)
+		z.c <- c // Send now to guarantee order
+		go writerCompressBlock(c, z.Header, data)
+		return nil
+	}
+
+	zdata := z.data[z.Header.BlockMaxSize:cap(z.data)]
 	// The compressed block size cannot exceed the input's.
 	var zn int
-	var err error
 
 	if level := z.Header.CompressionLevel; level != 0 {
-		zn, err = CompressBlockHC(data, z.zdata, level)
+		zn, _ = CompressBlockHC(data, zdata, level)
 	} else {
-		zn, err = CompressBlock(data, z.zdata, z.hashtable[:])
+		zn, _ = CompressBlock(data, zdata, z.hashtable[:])
 	}
 
-	var zdata []byte
 	var bLen uint32
 	if debugFlag {
 		debug("block compression %d => %d", len(data), zn)
 	}
-	if err == nil && zn > 0 && zn < len(data) {
+	if zn > 0 && zn < len(data) {
 		// Compressible and compressed size smaller than uncompressed: ok!
 		bLen = uint32(zn)
-		zdata = z.zdata[:zn]
+		zdata = zdata[:zn]
 	} else {
 		// Uncompressed block.
 		bLen = uint32(len(data)) | compressedBlockFlag
@@ -218,13 +298,35 @@
 		return nil
 	}
 
-	if err := z.compressBlock(z.data[:z.idx]); err != nil {
-		return err
-	}
+	data := z.data[:z.idx]
 	z.idx = 0
+	if z.c == nil {
+		return z.compressBlock(data)
+	}
+	if !z.NoChecksum {
+		_, _ = z.checksum.Write(data)
+	}
+	c := make(chan zResult)
+	z.c <- c
+	writerCompressBlock(c, z.Header, data)
 	return nil
 }
 
+func (z *Writer) close() error {
+	if z.c == nil {
+		return nil
+	}
+	// Send a sentinel block (no data to compress) to terminate the writer main goroutine.
+	c := make(chan zResult)
+	z.c <- c
+	c <- zResult{}
+	// Wait for the main goroutine to complete.
+	<-c
+	// At this point the main goroutine has shut down or is about to return.
+	z.c = nil
+	return z.err
+}
+
 // Close closes the Writer, flushing any unwritten data to the underlying io.Writer, but does not close the underlying io.Writer.
 func (z *Writer) Close() error {
 	if !z.Header.done {
@@ -235,6 +337,10 @@
 	if err := z.Flush(); err != nil {
 		return err
 	}
+	if err := z.close(); err != nil {
+		return err
+	}
+	z.freeBuffers()
 
 	if debugFlag {
 		debug("writing last empty block")
@@ -256,12 +362,15 @@
 // initial state from NewWriter, but instead writing to w.
 // No access to the underlying io.Writer is performed.
 func (z *Writer) Reset(w io.Writer) {
-	z.Header = Header{}
+	n := cap(z.c)
+	_ = z.close()
+	z.freeBuffers()
+	z.Header.Reset()
 	z.dst = w
 	z.checksum.Reset()
-	z.zdata = z.zdata[:0]
-	z.data = z.data[:0]
 	z.idx = 0
+	z.err = nil
+	z.WithConcurrency(n)
 }
 
 // writeUint32 writes a uint32 to the underlying writer.
@@ -271,3 +380,29 @@
 	_, err := z.dst.Write(buf)
 	return err
 }
+
+// writerCompressBlock compresses data into a pooled buffer and writes its result
+// out to the input channel.
+func writerCompressBlock(c chan zResult, header Header, data []byte) {
+	zdata := getBuffer(header.BlockMaxSize)
+	// The compressed block size cannot exceed the input's.
+	var zn int
+	if level := header.CompressionLevel; level != 0 {
+		zn, _ = CompressBlockHC(data, zdata, level)
+	} else {
+		var hashTable [winSize]int
+		zn, _ = CompressBlock(data, zdata, hashTable[:])
+	}
+	var res zResult
+	if zn > 0 && zn < len(data) {
+		res.size = uint32(zn)
+		res.data = zdata[:zn]
+	} else {
+		res.size = uint32(len(data)) | compressedBlockFlag
+		res.data = data
+	}
+	if header.BlockChecksum {
+		res.checksum = xxh32.ChecksumZero(res.data)
+	}
+	c <- res
+}