diff --git a/gfx/ipc/GPUParent.cpp b/gfx/ipc/GPUParent.cpp
index 43fc22babad6..102d2cc7a106 100644
--- a/gfx/ipc/GPUParent.cpp
+++ b/gfx/ipc/GPUParent.cpp
@@ -100,17 +100,17 @@ GPUParent* GPUParent::GetSingleton() {
   return sGPUParent;
 }
 
-/* static */ void GPUParent::MaybeFlushMemory() {
+/* static */ bool GPUParent::MaybeFlushMemory() {
 #if defined(XP_WIN) && !defined(HAVE_64BIT_BUILD)
   MOZ_ASSERT(CompositorThreadHolder::IsInCompositorThread());
   if (!XRE_IsGPUProcess()) {
-    return;
+    return false;
   }
 
   MEMORYSTATUSEX stat;
   stat.dwLength = sizeof(stat);
   if (!GlobalMemoryStatusEx(&stat)) {
-    return;
+    return false;
   }
 
   // We only care about virtual process memory space in the GPU process because
@@ -131,6 +131,9 @@ GPUParent* GPUParent::GetSingleton() {
         }));
   }
   sLowMemory = lowMemory;
+  return lowMemory;
+#else
+  return false;
 #endif
 }
 
diff --git a/gfx/ipc/GPUParent.h b/gfx/ipc/GPUParent.h
index b2051a4cc481..27daf79af318 100644
--- a/gfx/ipc/GPUParent.h
+++ b/gfx/ipc/GPUParent.h
@@ -34,7 +34,7 @@ class GPUParent final : public PGPUParent {
   static void GetGPUProcessName(nsACString& aStr);
 
   // Check for memory pressure and notify the parent process if necessary.
-  static void MaybeFlushMemory();
+  static bool MaybeFlushMemory();
 
   bool Init(base::ProcessId aParentPid, const char* aParentBuildID,
             MessageLoop* aIOLoop, UniquePtr<IPC::Channel> aChannel);
diff --git a/gfx/layers/wr/WebRenderBridgeParent.cpp b/gfx/layers/wr/WebRenderBridgeParent.cpp
index 7d2dde91a0a8..ea0e765b3c7f 100644
--- a/gfx/layers/wr/WebRenderBridgeParent.cpp
+++ b/gfx/layers/wr/WebRenderBridgeParent.cpp
@@ -485,8 +485,13 @@ bool WebRenderBridgeParent::UpdateResources(
   wr::ShmSegmentsReader reader(aSmallShmems, aLargeShmems);
   UniquePtr<ScheduleSharedSurfaceRelease> scheduleRelease;
 
-  if (!aResourceUpdates.IsEmpty()) {
-    GPUParent::MaybeFlushMemory();
+  while (GPUParent::MaybeFlushMemory()) {
+    // If the GPU process has memory pressure, preemptively unmap some of our
+    // shared memory images. If we are in the parent process, the expiration
+    // tracker itself will listen for the memory pressure event.
+    if (!SharedSurfacesParent::AgeAndExpireOneGeneration()) {
+      break;
+    }
   }
 
   for (const auto& cmd : aResourceUpdates) {