diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index ccdf54e81c..fc69570dcc 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -19,6 +19,7 @@
 
 #include "exec/memop.h"
 #include "standard-headers/linux/virtio_pci.h"
+#include "hw/boards.h"
 #include "hw/virtio/virtio.h"
 #include "migration/qemu-file-types.h"
 #include "hw/pci/pci.h"
@@ -2058,6 +2059,37 @@ void virtio_pci_types_register(const VirtioPCIDeviceTypeInfo *t)
     g_free(base_name);
 }
 
+unsigned virtio_pci_optimal_num_queues(unsigned fixed_queues)
+{
+    /*
+     * 1:1 vq to vCPU mapping is ideal because the same vCPU that submitted
+     * virtqueue buffers can handle their completion. When a different vCPU
+     * handles completion it may need to IPI the vCPU that submitted the
+     * request and this adds overhead.
+     *
+     * Virtqueues consume guest RAM and MSI-X vectors. This is wasteful in
+     * guests with very many vCPUs and a device that is only used by a few
+     * vCPUs. Unfortunately optimizing that case requires manual pinning inside
+     * the guest, so those users might as well manually set the number of
+     * queues. There is no upper limit that can be applied automatically and
+     * doing so arbitrarily would result in a sudden performance drop once the
+     * threshold number of vCPUs is exceeded.
+     */
+    unsigned num_queues = current_machine->smp.cpus;
+
+    /*
+     * The maximum number of MSI-X vectors is PCI_MSIX_FLAGS_QSIZE + 1, but the
+     * config change interrupt and the fixed virtqueues must be taken into
+     * account too.
+     */
+    num_queues = MIN(num_queues, PCI_MSIX_FLAGS_QSIZE - fixed_queues);
+
+    /*
+     * There is a limit to how many virtqueues a device can have.
+     */
+    return MIN(num_queues, VIRTIO_QUEUE_MAX - fixed_queues);
+}
+
 /* virtio-pci-bus */
 
 static void virtio_pci_bus_new(VirtioBusState *bus, size_t bus_size,
diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h
index e2eaaa9182..91096f0291 100644
--- a/hw/virtio/virtio-pci.h
+++ b/hw/virtio/virtio-pci.h
@@ -243,4 +243,13 @@ typedef struct VirtioPCIDeviceTypeInfo {
 /* Register virtio-pci type(s).  @t must be static. */
 void virtio_pci_types_register(const VirtioPCIDeviceTypeInfo *t);
 
+/**
+ * virtio_pci_optimal_num_queues:
+ * @fixed_queues: number of queues that are always present
+ *
+ * Returns: The optimal number of queues for a multi-queue device, excluding
+ * @fixed_queues.
+ */
+unsigned virtio_pci_optimal_num_queues(unsigned fixed_queues);
+
 #endif