syz-manager: make rpc communication finer grained

RPC package does excessive caching per connection,
so if a larger object is ever sent in any direction,
rpc connection consumes large amount of memory persistently.
This makes manager consume gigs of memory with large
number of VMs and larger corpus/coverage.

Make all communication done in very limited batches.

2 files changed, 27 insertions, 4 deletions

diff --git a/pkg/rpctype/rpctype.go b/pkg/rpctype/rpctype.go
index f5835914e..ead685c02 100644
--- a/pkg/rpctype/rpctype.go
+++ b/pkg/rpctype/rpctype.go
@@ -28,10 +28,6 @@ type ConnectArgs struct {
 }
 
 type ConnectRes struct {
-	Prios          [][]float32
-	Inputs         []RPCInput
-	MaxSignal      signal.Serial
-	Candidates     []RPCCandidate
 	EnabledCalls   []int
 	GitRevision    string
 	TargetRevision string
diff --git a/pkg/signal/signal.go b/pkg/signal/signal.go
index e82255537..20deba46a 100644
--- a/pkg/signal/signal.go
+++ b/pkg/signal/signal.go
@@ -28,6 +28,33 @@ func (s Signal) Empty() bool {
 	return len(s) == 0
 }
 
+func (s Signal) Copy() Signal {
+	c := make(Signal, len(s))
+	for e, p := range s {
+		c[e] = p
+	}
+	return c
+}
+
+func (s *Signal) Split(n int) Signal {
+	if s.Empty() {
+		return nil
+	}
+	c := make(Signal, n)
+	for e, p := range *s {
+		delete(*s, e)
+		c[e] = p
+		n--
+		if n == 0 {
+			break
+		}
+	}
+	if len(*s) == 0 {
+		*s = nil
+	}
+	return c
+}
+
 func FromRaw(raw []uint32, prio uint8) Signal {
 	if len(raw) == 0 {
 		return nil