| Index: impl/prod/memcache.go | 
| diff --git a/impl/prod/memcache.go b/impl/prod/memcache.go | 
| index 5b7b4c456b01c0ed44c33757b86fcd0818ec9669..cc4a3d1824008de3623416f7e556257d06d3ecf9 100644 | 
| --- a/impl/prod/memcache.go | 
| +++ b/impl/prod/memcache.go | 
| @@ -8,15 +8,15 @@ import ( | 
| "time" | 
|  | 
| mc "github.com/luci/gae/service/memcache" | 
| -	"github.com/luci/luci-go/common/errors" | 
| "golang.org/x/net/context" | 
| +	"google.golang.org/appengine" | 
| "google.golang.org/appengine/memcache" | 
| ) | 
|  | 
| // useMC adds a gae.Memcache implementation to context, accessible | 
| // by gae.GetMC(c) | 
| func useMC(c context.Context) context.Context { | 
| -	return mc.SetFactory(c, func(ci context.Context) mc.Interface { | 
| +	return mc.SetRawFactory(c, func(ci context.Context) mc.RawInterface { | 
| return mcImpl{ci} | 
| }) | 
| } | 
| @@ -31,7 +31,6 @@ var _ mc.Item = mcItem{} | 
|  | 
| func (i mcItem) Key() string               { return i.i.Key } | 
| func (i mcItem) Value() []byte             { return i.i.Value } | 
| -func (i mcItem) Object() interface{}       { return i.i.Object } | 
| func (i mcItem) Flags() uint32             { return i.i.Flags } | 
| func (i mcItem) Expiration() time.Duration { return i.i.Expiration } | 
|  | 
| @@ -43,10 +42,6 @@ func (i mcItem) SetValue(v []byte) mc.Item { | 
| i.i.Value = v | 
| return i | 
| } | 
| -func (i mcItem) SetObject(o interface{}) mc.Item { | 
| -	i.i.Object = o | 
| -	return i | 
| -} | 
| func (i mcItem) SetFlags(f uint32) mc.Item { | 
| i.i.Flags = f | 
| return i | 
| @@ -56,6 +51,14 @@ func (i mcItem) SetExpiration(d time.Duration) mc.Item { | 
| return i | 
| } | 
|  | 
| +func (i mcItem) SetAll(other mc.Item) { | 
| +	o := other.(mcItem) | 
| +	*i.i = *o.i | 
| +	val := i.i.Value | 
| +	i.i.Value = make([]byte, len(val)) | 
| +	copy(i.i.Value, val) | 
| +} | 
| + | 
| // mcR2FErr (MC real-to-fake w/ error) converts a *memcache.Item to a mc.Item, | 
| // and passes along an error. | 
| func mcR2FErr(i *memcache.Item, err error) (mc.Item, error) { | 
| @@ -91,62 +94,60 @@ func (m mcImpl) NewItem(key string) mc.Item { | 
| return mcItem{&memcache.Item{Key: key}} | 
| } | 
|  | 
| -//////// MCSingleReadWriter | 
| -func (m mcImpl) Add(item mc.Item) error { | 
| -	return memcache.Add(m.Context, mcF2R(item)) | 
| -} | 
| -func (m mcImpl) Set(item mc.Item) error { | 
| -	return memcache.Set(m.Context, mcF2R(item)) | 
| -} | 
| -func (m mcImpl) Delete(key string) error { | 
| -	return memcache.Delete(m.Context, key) | 
| -} | 
| -func (m mcImpl) Get(key string) (mc.Item, error) { | 
| -	return mcR2FErr(memcache.Get(m.Context, key)) | 
| -} | 
| -func (m mcImpl) CompareAndSwap(item mc.Item) error { | 
| -	return memcache.CompareAndSwap(m.Context, mcF2R(item)) | 
| +func doCB(err error, cb mc.RawCB) error { | 
| +	if me, ok := err.(appengine.MultiError); ok { | 
| +		for _, err := range me { | 
| +			cb(err) | 
| +		} | 
| +		err = nil | 
| +	} | 
| +	return err | 
| } | 
|  | 
| -//////// MCMultiReadWriter | 
| -func (m mcImpl) DeleteMulti(keys []string) error { | 
| -	return errors.Fix(memcache.DeleteMulti(m.Context, keys)) | 
| +func (m mcImpl) DeleteMulti(keys []string, cb mc.RawCB) error { | 
| +	return doCB(memcache.DeleteMulti(m.Context, keys), cb) | 
| } | 
| -func (m mcImpl) AddMulti(items []mc.Item) error { | 
| -	return errors.Fix(memcache.AddMulti(m.Context, mcMF2R(items))) | 
| + | 
| +func (m mcImpl) AddMulti(items []mc.Item, cb mc.RawCB) error { | 
| +	return doCB(memcache.AddMulti(m.Context, mcMF2R(items)), cb) | 
| } | 
| -func (m mcImpl) SetMulti(items []mc.Item) error { | 
| -	return errors.Fix(memcache.SetMulti(m.Context, mcMF2R(items))) | 
| + | 
| +func (m mcImpl) SetMulti(items []mc.Item, cb mc.RawCB) error { | 
| +	return doCB(memcache.SetMulti(m.Context, mcMF2R(items)), cb) | 
| } | 
| -func (m mcImpl) GetMulti(keys []string) (map[string]mc.Item, error) { | 
| + | 
| +func (m mcImpl) GetMulti(keys []string, cb mc.RawItemCB) error { | 
| realItems, err := memcache.GetMulti(m.Context, keys) | 
| if err != nil { | 
| -		return nil, errors.Fix(err) | 
| +		return err | 
| } | 
| -	items := make(map[string]mc.Item, len(realItems)) | 
| -	for k, itm := range realItems { | 
| -		items[k] = mcItem{itm} | 
| +	for _, k := range keys { | 
| +		itm := realItems[k] | 
| +		if itm == nil { | 
| +			cb(nil, memcache.ErrCacheMiss) | 
| +		} else { | 
| +			cb(mcItem{itm}, nil) | 
| +		} | 
| } | 
| -	return items, err | 
| -} | 
| -func (m mcImpl) CompareAndSwapMulti(items []mc.Item) error { | 
| -	return errors.Fix(memcache.CompareAndSwapMulti(m.Context, mcMF2R(items))) | 
| +	return nil | 
| } | 
|  | 
| -//////// MCIncrementer | 
| -func (m mcImpl) Increment(key string, delta int64, initialValue uint64) (uint64, error) { | 
| -	return memcache.Increment(m.Context, key, delta, initialValue) | 
| +func (m mcImpl) CompareAndSwapMulti(items []mc.Item, cb mc.RawCB) error { | 
| +	return doCB(memcache.CompareAndSwapMulti(m.Context, mcMF2R(items)), cb) | 
| } | 
| -func (m mcImpl) IncrementExisting(key string, delta int64) (uint64, error) { | 
| -	return memcache.IncrementExisting(m.Context, key, delta) | 
| + | 
| +func (m mcImpl) Increment(key string, delta int64, initialValue *uint64) (uint64, error) { | 
| +	if initialValue == nil { | 
| +		return memcache.IncrementExisting(m.Context, key, delta) | 
| +	} else { | 
| +		return memcache.Increment(m.Context, key, delta, *initialValue) | 
| +	} | 
| } | 
|  | 
| -//////// MCFlusher | 
| func (m mcImpl) Flush() error { | 
| return memcache.Flush(m.Context) | 
| } | 
|  | 
| -//////// MCStatter | 
| func (m mcImpl) Stats() (*mc.Statistics, error) { | 
| stats, err := memcache.Stats(m.Context) | 
| if err != nil { | 
|  |