diff --git a/packages/ludic.render3d/env.ludic b/packages/ludic.render3d/env.ludic
index d1258cfc..be635281 100644
--- a/packages/ludic.render3d/env.ludic
+++ b/packages/ludic.render3d/env.ludic
@@ -196,6 +196,9 @@ export state Render3dState {
   gvk_al_off: []int = null
   gvk_al_len: []int = null
   gvk_al_map: []pointer = null
+  gvk_al_tag: []int = null          # per allocation id: owner * 4 + image * 2 + host (vkmem_report.ludic)
+  gvk_tag: int = 0                  # the owner allocations are made for now (VKM_*)
+  vkmem_at: int = 0                 # R3D_VKMEM=<frame>: the report is printed at that frame
   @max(4096) gvk_al_spare: []int = null        # ids to reuse
   gvk_pool: long = 0
   gvk_fence: bytes = null
diff --git a/packages/ludic.render3d/gltf.ludic b/packages/ludic.render3d/gltf.ludic
index f3804237..8710c4f5 100644
--- a/packages/ludic.render3d/gltf.ludic
+++ b/packages/ludic.render3d/gltf.ludic
@@ -175,9 +175,17 @@ function gltf_prim(render3d_st: mut Render3dState, p: Val) -> Prim {
 }
 
 # Load the mesh of the node called `node_name` from dir/file.
+# the GPU memory it makes is counted as VKM_MODEL (R3D_VKMEM)
+function gltf_load(render3d_st: mut Render3dState, dir: string, file: string, node_name: string) -> Model {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_MODEL
+  let r = gltf_load__t(render3d_st, dir, file, node_name)
+  render3d_st.gvk_tag = was
+  return r
+}
 @alloc_ok("loading a model, a texture or a font: a load, not a frame (a guest loading a teammate's look is one)")
 @creates(Model)
-function gltf_load(render3d_st: mut Render3dState, dir: string, file: string, node_name: string) -> Model {
+function gltf_load__t(render3d_st: mut Render3dState, dir: string, file: string, node_name: string) -> Model {
   render3d_st.gltf_dir = dir
   let at = dir + "/" + file
   let text = Fs.read_text(at)
diff --git a/packages/ludic.render3d/gpu_vk.ludic b/packages/ludic.render3d/gpu_vk.ludic
index 4360ceb5..cd558857 100644
--- a/packages/ludic.render3d/gpu_vk.ludic
+++ b/packages/ludic.render3d/gpu_vk.ludic
@@ -358,7 +358,8 @@ function gvk_mem_init(render3d_st: mut Render3dState) -> void {
   render3d_st.gvk_blk_mem = new []long;  render3d_st.gvk_blk_kind = new []int;  render3d_st.gvk_blk_size = new []int;  render3d_st.gvk_blk_map = new []pointer
   render3d_st.gvk_fr_blk = new []int;  render3d_st.gvk_fr_off = new []int;  render3d_st.gvk_fr_len = new []int
   render3d_st.gvk_al_blk = new []int;  render3d_st.gvk_al_mem = new []long;  render3d_st.gvk_al_off = new []int;  render3d_st.gvk_al_len = new []int
-  render3d_st.gvk_al_map = new []pointer;  render3d_st.gvk_al_spare = new []int
+  render3d_st.gvk_al_map = new []pointer;  render3d_st.gvk_al_spare = new []int;  render3d_st.gvk_al_tag = new []int
+  push(render3d_st.gvk_al_tag, 0)
   push(render3d_st.gvk_al_blk, -1);  push(render3d_st.gvk_al_mem, zero);  push(render3d_st.gvk_al_off, 0);  push(render3d_st.gvk_al_len, 0);  push(render3d_st.gvk_al_map, null)
 }
 
@@ -483,10 +484,15 @@ function gvk_mem_new(render3d_st: mut Render3dState, req: bytes, want: int, imag
     List.pop(spare)
   } else {
     push(render3d_st.gvk_al_blk, -1);  push(render3d_st.gvk_al_mem, zero);  push(render3d_st.gvk_al_off, 0);  push(render3d_st.gvk_al_len, 0);  push(render3d_st.gvk_al_map, null)
+    push(render3d_st.gvk_al_tag, 0)
     a = len(render3d_st.gvk_al_blk) - 1
   }
   var len_ = size
   if blk >= 0 { len_ = span }                 # what the block gives back when it is freed
+  var tg = render3d_st.gvk_tag * 4
+  if image { tg += 2 }
+  if host { tg += 1 }
+  render3d_st.gvk_al_tag[a] = tg
   render3d_st.gvk_al_blk[a] = blk;  render3d_st.gvk_al_mem[a] = own;  render3d_st.gvk_al_off[a] = off;  render3d_st.gvk_al_len[a] = len_;  render3d_st.gvk_al_map[a] = map
   return a
 }
diff --git a/packages/ludic.render3d/grass.ludic b/packages/ludic.render3d/grass.ludic
index 319ec959..6059d5d3 100644
--- a/packages/ludic.render3d/grass.ludic
+++ b/packages/ludic.render3d/grass.ludic
@@ -87,8 +87,15 @@ function grass_blade_mesh(render3d_st: mut Render3dState, rows: int) -> Mesh {
   return m
 }
 
-@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+# the GPU memory it makes is counted as VKM_GRASS (R3D_VKMEM)
 function grass_init(render3d_st: mut Render3dState) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_GRASS
+  grass_init__t(render3d_st)
+  render3d_st.gvk_tag = was
+}
+@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+function grass_init__t(render3d_st: mut Render3dState) -> void {
   render3d_st.grass_merge = gpu_has_mdi(render3d_st) and not r3d_env_has(render3d_st, "R3D_GRASS_TILES")
   var defs = "#define FOLIAGE\n#define BLADE\n#define GBLADE\n"
   if render3d_st.grass_merge {
diff --git a/packages/ludic.render3d/grass_gpu.ludic b/packages/ludic.render3d/grass_gpu.ludic
index add91d4c..6849d712 100644
--- a/packages/ludic.render3d/grass_gpu.ludic
+++ b/packages/ludic.render3d/grass_gpu.ludic
@@ -26,8 +26,15 @@ function gg_base(b: int) -> int {
 }
 
 # once, after grass_init: the programs, the buffers and the three instanced blades
-@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+# the GPU memory it makes is counted as VKM_GRASS (R3D_VKMEM)
 function gg_init(render3d_st: mut Render3dState) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_GRASS
+  gg_init__t(render3d_st)
+  render3d_st.gvk_tag = was
+}
+@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+function gg_init__t(render3d_st: mut Render3dState) -> void {
   if not gpu_has_compute(render3d_st) or render3d_st.grass_prog == 0 { return }
   if r3d_env_has(render3d_st, "R3D_GRASS_GPU") and r3d_env(render3d_st, "R3D_GRASS_GPU") == "0" { return }
   render3d_st.gg_reset = gpu_compute(render3d_st, "grass_reset", 1)
diff --git a/packages/ludic.render3d/post.ludic b/packages/ludic.render3d/post.ludic
index f00dc685..83c45632 100644
--- a/packages/ludic.render3d/post.ludic
+++ b/packages/ludic.render3d/post.ludic
@@ -54,8 +54,15 @@ function post_set_msaa(render3d_st: mut Render3dState, n: int) -> void {
   }
 }
 
-@alloc_ok("a world being set up (a stream, a layer, water, post, a bake): the map loading or swapping, not a frame")
+# the GPU memory it makes is counted as VKM_TARGET (R3D_VKMEM)
 function post_init(render3d_st: mut Render3dState, w: int, h: int) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_TARGET
+  post_init__t(render3d_st, w, h)
+  render3d_st.gvk_tag = was
+}
+@alloc_ok("a world being set up (a stream, a layer, water, post, a bake): the map loading or swapping, not a frame")
+function post_init__t(render3d_st: mut Render3dState, w: int, h: int) -> void {
   render3d_st.post_w = w;  render3d_st.post_h = h
   # the exposure's two 1x1 targets: made once, here, rather than by the first frame that measured
   if render3d_st.post_adapt_t == null {
diff --git a/packages/ludic.render3d/r3d.ludic b/packages/ludic.render3d/r3d.ludic
index 4a9237bc..5b29e05e 100644
--- a/packages/ludic.render3d/r3d.ludic
+++ b/packages/ludic.render3d/r3d.ludic
@@ -10,6 +10,7 @@ import "fmath.ludic"
 import "gpu.ludic"
 import "gpu_manifest.ludic"
 import "gpu_vk.ludic"
+import "vkmem_report.ludic"
 import "gpu_vk_res.ludic"
 import "gpu_vk_bc.ludic"
 import "texture_dds.ludic"
diff --git a/packages/ludic.render3d/render.ludic b/packages/ludic.render3d/render.ludic
index 9532fe44..42959189 100644
--- a/packages/ludic.render3d/render.ludic
+++ b/packages/ludic.render3d/render.ludic
@@ -190,7 +190,14 @@ function r3d_screenshot(render3d_st: mut Render3dState, path: string) -> bool {
 function r3d_present(render3d_st: mut Render3dState) -> void { gpu_present(render3d_st) }
 
 # the drawable changed size: the camera's aspect and every screen-sized target follow
+# the GPU memory it makes is counted as VKM_TARGET (R3D_VKMEM)
 function r3d_resize(render3d_st: mut Render3dState) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_TARGET
+  r3d_resize__t(render3d_st)
+  render3d_st.gvk_tag = was
+}
+function r3d_resize__t(render3d_st: mut Render3dState) -> void {
   render3d_st.cam_aspect = float(gl_width()) / float(gl_height())
   cam_update(render3d_st)
   post_free(render3d_st)
@@ -198,7 +205,14 @@ function r3d_resize(render3d_st: mut Render3dState) -> void {
   if render3d_st.water_refl != null { target_free(render3d_st, render3d_st.water_refl);  render3d_st.water_refl = null }
   r3d_say_resized()
 }
+# the GPU memory it makes is counted as VKM_FRAME (R3D_VKMEM)
 function r3d_frame(render3d_st: mut Render3dState, time: float) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_FRAME
+  r3d_frame__t(render3d_st, time)
+  render3d_st.gvk_tag = was
+}
+function r3d_frame__t(render3d_st: mut Render3dState, time: float) -> void {
   outline_frame(render3d_st)
   if not render3d_st.r3d_ready { return }
   if gpu_resize_check(render3d_st) { r3d_resize(render3d_st) }
@@ -206,6 +220,7 @@ function r3d_frame(render3d_st: mut Render3dState, time: float) -> void {
   # or a fullscreen change does. Headless has no window to resize, and this path is where
   # a stale attachment or a texture freed twice shows up.
   render3d_st.r3d_test_frame += 1
+  vkmem_tick(render3d_st)
   if render3d_st.r3d_test_resize == 0 and r3d_env_has(render3d_st, "R3D_RESIZE_AT") { render3d_st.r3d_test_resize = Text.to_int(r3d_env(render3d_st, "R3D_RESIZE_AT")) }
   # R3D_RESIZE_AT=<n>: from frame n on, rebuild every screen-sized buffer every few
   # frames at a different size, as dragging a window edge or entering fullscreen does.
diff --git a/packages/ludic.render3d/scatter.ludic b/packages/ludic.render3d/scatter.ludic
index 5bcfac85..9f489019 100644
--- a/packages/ludic.render3d/scatter.ludic
+++ b/packages/ludic.render3d/scatter.ludic
@@ -248,8 +248,16 @@ function scatter_attach(render3d_st: Render3dState, m: Mesh, buf: int) -> void {
   gpu_mesh_done(render3d_st, m)
 }
 
-@alloc_ok("a world being set up (a stream, a layer, water, post, a bake): the map loading or swapping, not a frame")
+# the GPU memory it makes is counted as VKM_SCATTER (R3D_VKMEM)
 function layer_new(render3d_st: mut Render3dState, model: Model, cap: int, foliage: bool, wind: float, near: float, cull: float) -> Layer {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_SCATTER
+  let r = layer_new__t(render3d_st, model, cap, foliage, wind, near, cull)
+  render3d_st.gvk_tag = was
+  return r
+}
+@alloc_ok("a world being set up (a stream, a layer, water, post, a bake): the map loading or swapping, not a frame")
+function layer_new__t(render3d_st: mut Render3dState, model: Model, cap: int, foliage: bool, wind: float, near: float, cull: float) -> Layer {
   let l = new Layer
   l.model = model
   l.cap = cap
@@ -301,8 +309,16 @@ function layer_add(l: Layer, x: float, y: float, z: float, scale: float, yaw: fl
 }
 
 # ---- impostors ---------------------------------------------------------------------
-@alloc_ok("a world being set up (a stream, a layer, water, post, a bake): the map loading or swapping, not a frame")
+# the GPU memory it makes is counted as VKM_IMPOSTOR (R3D_VKMEM)
 function impostor_bake(render3d_st: mut Render3dState, model: Model, tiles: int, tw: int, th: int) -> Impostor {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_IMPOSTOR
+  let r = impostor_bake__t(render3d_st, model, tiles, tw, th)
+  render3d_st.gvk_tag = was
+  return r
+}
+@alloc_ok("a world being set up (a stream, a layer, water, post, a bake): the map loading or swapping, not a frame")
+function impostor_bake__t(render3d_st: mut Render3dState, model: Model, tiles: int, tw: int, th: int) -> Impostor {
   let im = new Impostor
   im.tiles = tiles
   im.radius = model.radius * 1.02
@@ -1113,7 +1129,15 @@ function cb_rnd(render3d_st: mut Render3dState) -> float {
   render3d_st.cb_state = (render3d_st.cb_state * 1103515245 + 12345) & 0x7FFFFFFF
   return float((render3d_st.cb_state >> 8) & 0xFFFF) / 65536.0
 }
+# the GPU memory it makes is counted as VKM_SCATTER (R3D_VKMEM)
 function carpet_bake(render3d_st: mut Render3dState, layers: []Layer, count: int, tile: float, res: int) -> int {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_SCATTER
+  let r = carpet_bake__t(render3d_st, layers, count, tile, res)
+  render3d_st.gvk_tag = was
+  return r
+}
+function carpet_bake__t(render3d_st: mut Render3dState, layers: []Layer, count: int, tile: float, res: int) -> int {
   let tex = tex_target(render3d_st, res, res, GL_RGBA8, GL_RGBA, GL_UNSIGNED_BYTE, GL_LINEAR)
   let fbo = gpu_fb_new(render3d_st)
   gpu_fb_bind(render3d_st, fbo)
diff --git a/packages/ludic.render3d/shadow.ludic b/packages/ludic.render3d/shadow.ludic
index ddbd024a..94c75eaf 100644
--- a/packages/ludic.render3d/shadow.ludic
+++ b/packages/ludic.render3d/shadow.ludic
@@ -8,8 +8,15 @@
 const SHADOW_CASCADES: int = 5
 
 
-@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+# the GPU memory it makes is counted as VKM_SHADOW (R3D_VKMEM)
 function shadow_init(render3d_st: mut Render3dState) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_SHADOW
+  shadow_init__t(render3d_st)
+  render3d_st.gvk_tag = was
+}
+@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+function shadow_init__t(render3d_st: mut Render3dState) -> void {
   shadow_make_tex(render3d_st)
   render3d_st.sh_fbo = gpu_fb_new(render3d_st)
   gpu_fb_bind(render3d_st, render3d_st.sh_fbo)
diff --git a/packages/ludic.render3d/sky.ludic b/packages/ludic.render3d/sky.ludic
index acc40811..06f03381 100644
--- a/packages/ludic.render3d/sky.ludic
+++ b/packages/ludic.render3d/sky.ludic
@@ -37,8 +37,16 @@ function sky_dir_from_uv(o: floats, u: float, v: float) -> void {
   v3_set(o, st * Math.sin(phi), Math.cos(theta), -(st * Math.cos(phi)))
 }
 
-@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+# the GPU memory it makes is counted as VKM_SKY (R3D_VKMEM)
 function sky_load(render3d_st: mut Render3dState, path: string) -> bool {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_SKY
+  let r = sky_load__t(render3d_st, path)
+  render3d_st.gvk_tag = was
+  return r
+}
+@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+function sky_load__t(render3d_st: mut Render3dState, path: string) -> bool {
   render3d_st.sky_tex = tex_load_hdr(render3d_st, path)
   if render3d_st.sky_tex == 0 { return false }
   render3d_st.sky_w = render3d_st.tex_w;  render3d_st.sky_h = render3d_st.tex_h
diff --git a/packages/ludic.render3d/stream.ludic b/packages/ludic.render3d/stream.ludic
index b1ffc818..8e00126b 100644
--- a/packages/ludic.render3d/stream.ludic
+++ b/packages/ludic.render3d/stream.ludic
@@ -44,8 +44,16 @@ property Stream {
 
 # microseconds spent per frame, split so the hitch can be attributed (R3D_PROF=1)
 
-@alloc_ok("a world being set up (a stream, a layer, water, post, a bake): the map loading or swapping, not a frame")
+# the GPU memory it makes is counted as VKM_SCATTER (R3D_VKMEM)
 function stream_new(render3d_st: mut Render3dState, layer: Layer, size: float, reach: float, b0: float, b1: float, b2: float, b3: float) -> Stream {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_SCATTER
+  let r = stream_new__t(render3d_st, layer, size, reach, b0, b1, b2, b3)
+  render3d_st.gvk_tag = was
+  return r
+}
+@alloc_ok("a world being set up (a stream, a layer, water, post, a bake): the map loading or swapping, not a frame")
+function stream_new__t(render3d_st: mut Render3dState, layer: Layer, size: float, reach: float, b0: float, b1: float, b2: float, b3: float) -> Stream {
   if not render3d_st.stream_cap_read {
     render3d_st.stream_cap_read = true
     if r3d_env_has(render3d_st, "R3D_STREAM_CAP") { render3d_st.STREAM_MAX_CHUNKS = Text.to_int(r3d_env(render3d_st, "R3D_STREAM_CAP")) }
diff --git a/packages/ludic.render3d/terrain.ludic b/packages/ludic.render3d/terrain.ludic
index 01706e83..be41d0cf 100644
--- a/packages/ludic.render3d/terrain.ludic
+++ b/packages/ludic.render3d/terrain.ludic
@@ -142,7 +142,14 @@ function terrain_ortho_forest(render3d_st: mut Render3dState, x: float, z: float
   return 0.0
 }
 
+# the GPU memory it makes is counted as VKM_TERRAIN (R3D_VKMEM)
 function terrain_use_ortho(render3d_st: mut Render3dState, path: string) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_TERRAIN
+  terrain_use_ortho__t(render3d_st, path)
+  render3d_st.gvk_tag = was
+}
+function terrain_use_ortho__t(render3d_st: mut Render3dState, path: string) -> void {
   let px = png_decode(render3d_st, path)
   if px == null { return }
   # a map set up over another lets go of the last one's photograph first
@@ -156,7 +163,14 @@ function terrain_use_ortho(render3d_st: mut Render3dState, path: string) -> void
   gpu_tex_param(render3d_st, GPU_TEX2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE)
   gpu_tex_param(render3d_st, GPU_TEX2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE)
 }
+# the GPU memory it makes is counted as VKM_TERRAIN (R3D_VKMEM)
 function terrain_use_dem(render3d_st: mut Render3dState, path: string, emin: float, emax: float, base: float, ox: float, oz: float) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_TERRAIN
+  terrain_use_dem__t(render3d_st, path, emin, emax, base, ox, oz)
+  render3d_st.gvk_tag = was
+}
+function terrain_use_dem__t(render3d_st: mut Render3dState, path: string, emin: float, emax: float, base: float, ox: float, oz: float) -> void {
   if render3d_st.ter_dem_tex != 0 { gpu_tex_free(render3d_st, render3d_st.ter_dem_tex) }
   render3d_st.ter_dem_tex = tex_load(render3d_st, path, false)
   render3d_st.ter_dem_min = emin;  render3d_st.ter_dem_max = emax;  render3d_st.ter_dem_base = base
@@ -166,7 +180,14 @@ function terrain_use_dem(render3d_st: mut Render3dState, path: string, emin: flo
   gpu_tex_param(render3d_st, GPU_TEX2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE)
 }
 
+# the GPU memory it makes is counted as VKM_TERRAIN (R3D_VKMEM)
 function terrain_generate(render3d_st: mut Render3dState) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_TERRAIN
+  terrain_generate__t(render3d_st)
+  render3d_st.gvk_tag = was
+}
+function terrain_generate__t(render3d_st: mut Render3dState) -> void {
   var defs = ""
   if render3d_st.ter_dem_tex != 0 { defs = "#define DEM\n" }
   if render3d_st.ter_smooth { defs = "#define SMOOTH\n" }
@@ -324,8 +345,15 @@ function terrain_height_smooth(render3d_st: mut Render3dState, x: float, z: floa
   return h
 }
 
-@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+# the GPU memory it makes is counted as VKM_TERRAIN (R3D_VKMEM)
 function terrain_load_textures(render3d_st: mut Render3dState) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_TERRAIN
+  terrain_load_textures__t(render3d_st)
+  render3d_st.gvk_tag = was
+}
+@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+function terrain_load_textures__t(render3d_st: mut Render3dState) -> void {
   render3d_st.ter_tex = words(15)
   let a = render3d_st.r3d_assets + "/textures/"
   render3d_st.ter_tex[0] = tex_load(render3d_st, a + "aerial_grass_rock_diff_2k.png", true)
@@ -346,7 +374,14 @@ function terrain_load_textures(render3d_st: mut Render3dState) -> void {
   if r3d_env_has(render3d_st, "R3D_TEXDBG") { for i in 0 .. 15 { print(`ter_tex[{string(i)}] = {string(render3d_st.ter_tex[i])}`) } }
 }
 
+# the GPU memory it makes is counted as VKM_TERRAIN (R3D_VKMEM)
 function terrain_init(render3d_st: mut Render3dState) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_TERRAIN
+  terrain_init__t(render3d_st)
+  render3d_st.gvk_tag = was
+}
+function terrain_init__t(render3d_st: mut Render3dState) -> void {
   for i in 0 .. TERRAIN_INIT_STEPS { terrain_init_step(render3d_st, i) }
 }
 
@@ -361,8 +396,15 @@ function terrain_init_step(render3d_st: mut Render3dState, i: int) -> void {
   terrain_init_finish(render3d_st)
 }
 
-@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+# the GPU memory it makes is counted as VKM_TERRAIN (R3D_VKMEM)
 function terrain_init_finish(render3d_st: mut Render3dState) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_TERRAIN
+  terrain_init_finish__t(render3d_st)
+  render3d_st.gvk_tag = was
+}
+@alloc_ok("start-up: the device, its tables, the programs, the passes and the world's first textures are made once, before play")
+function terrain_init_finish__t(render3d_st: mut Render3dState) -> void {
   cdlod_init(render3d_st)
   render3d_st.ter_wire = r3d_env_has(render3d_st, "R3D_WIRE")
   render3d_st.ter_force_far = r3d_env_has(render3d_st, "R3D_TFARONLY")
diff --git a/packages/ludic.render3d/texture.ludic b/packages/ludic.render3d/texture.ludic
index e7a7f60c..48ab06f6 100644
--- a/packages/ludic.render3d/texture.ludic
+++ b/packages/ludic.render3d/texture.ludic
@@ -265,8 +265,16 @@ function tex_upload(render3d_st: mut Render3dState, px: pointer, srgb: bool, mip
 @alloc_ok("loading a model, a texture or a font: a load, not a frame (a guest loading a teammate's look is one)")
 function tex_load(render3d_st: mut Render3dState, path: pointer, srgb: bool) -> int { return tex_load_ex(render3d_st, path, srgb, 0) }
 # ... with `dilate` passes of edge padding for a cut-out atlas (0 = none)
-@alloc_ok("loading a model, a texture or a font: a load, not a frame (a guest loading a teammate's look is one)")
+# the GPU memory it makes is counted as VKM_TEXTURE (R3D_VKMEM)
 function tex_load_ex(render3d_st: mut Render3dState, path: pointer, srgb: bool, dilate: int) -> int {
+  let was = render3d_st.gvk_tag
+  if was == VKM_OTHER { render3d_st.gvk_tag = VKM_TEXTURE }
+  let r = tex_load_ex__t(render3d_st, path, srgb, dilate)
+  render3d_st.gvk_tag = was
+  return r
+}
+@alloc_ok("loading a model, a texture or a font: a load, not a frame (a guest loading a teammate's look is one)")
+function tex_load_ex__t(render3d_st: mut Render3dState, path: pointer, srgb: bool, dilate: int) -> int {
   # a .dds encoded beside the .png at build time goes to the GPU compressed, its mips included
   # (not for a cut-out atlas: its edge padding is made here, from the .png)
   if render3d_st.gvk_has_bc and dilate == 0 {
@@ -410,7 +418,15 @@ function hdr_decode(render3d_st: mut Render3dState, path: pointer) -> floats {
 }
 
 # Load an equirectangular .hdr as an RGB16F texture with mips (clamped in v).
+# the GPU memory it makes is counted as VKM_TEXTURE (R3D_VKMEM)
 function tex_load_hdr(render3d_st: mut Render3dState, path: pointer) -> int {
+  let was = render3d_st.gvk_tag
+  if was == VKM_OTHER { render3d_st.gvk_tag = VKM_TEXTURE }
+  let r = tex_load_hdr__t(render3d_st, path)
+  render3d_st.gvk_tag = was
+  return r
+}
+function tex_load_hdr__t(render3d_st: mut Render3dState, path: pointer) -> int {
   let px = hdr_decode(render3d_st, path)
   if px == null { return 0 }
   let id = gpu_tex_new(render3d_st)
@@ -484,8 +500,16 @@ function tex_dump(render3d_st: mut Render3dState, tex: int, w: int, h: int, path
 
 # A binary PPM (P6, what Gl.screenshot writes) as an RGB8 texture, box-filtered down by
 # `shrink` (a photo thumbnail); 0 when the file is missing.
-@alloc_ok("a load: an image read from disk")
+# the GPU memory it makes is counted as VKM_TEXTURE (R3D_VKMEM)
 function tex_load_ppm(render3d_st: mut Render3dState, path: pointer, shrink: int) -> int {
+  let was = render3d_st.gvk_tag
+  if was == VKM_OTHER { render3d_st.gvk_tag = VKM_TEXTURE }
+  let r = tex_load_ppm__t(render3d_st, path, shrink)
+  render3d_st.gvk_tag = was
+  return r
+}
+@alloc_ok("a load: an image read from disk")
+function tex_load_ppm__t(render3d_st: mut Render3dState, path: pointer, shrink: int) -> int {
   let d = r3d_read_file(render3d_st, path)
   if d == null { return 0 }
   let size = render3d_st.tex_file_len
diff --git a/packages/ludic.render3d/texture_dds.ludic b/packages/ludic.render3d/texture_dds.ludic
index 71b90e06..58a4b024 100644
--- a/packages/ludic.render3d/texture_dds.ludic
+++ b/packages/ludic.render3d/texture_dds.ludic
@@ -18,8 +18,16 @@ function dds_path_of(path: string) -> string {
 }
 
 # Load the .dds at `path` as a texture (srgb: colour, sampled as sRGB), or 0
-@alloc_ok("loading a model, a texture or a font: a load, not a frame (a guest loading a teammate's look is one)")
+# the GPU memory it makes is counted as VKM_TEXTURE (R3D_VKMEM)
 function tex_load_dds(render3d_st: mut Render3dState, path: string, srgb: bool) -> int {
+  let was = render3d_st.gvk_tag
+  if was == VKM_OTHER { render3d_st.gvk_tag = VKM_TEXTURE }
+  let r = tex_load_dds__t(render3d_st, path, srgb)
+  render3d_st.gvk_tag = was
+  return r
+}
+@alloc_ok("loading a model, a texture or a font: a load, not a frame (a guest loading a teammate's look is one)")
+function tex_load_dds__t(render3d_st: mut Render3dState, path: string, srgb: bool) -> int {
   let b = Fs.read_bytes(path)
   if b == null { return 0 }
   let id = tex_load_dds_bytes(render3d_st, b, srgb)
@@ -28,7 +36,15 @@ function tex_load_dds(render3d_st: mut Render3dState, path: string, srgb: bool)
   return id
 }
 
+# the GPU memory it makes is counted as VKM_TEXTURE (R3D_VKMEM)
 function tex_load_dds_bytes(render3d_st: mut Render3dState, b: []byte, srgb: bool) -> int {
+  let was = render3d_st.gvk_tag
+  if was == VKM_OTHER { render3d_st.gvk_tag = VKM_TEXTURE }
+  let r = tex_load_dds_bytes__t(render3d_st, b, srgb)
+  render3d_st.gvk_tag = was
+  return r
+}
+function tex_load_dds_bytes__t(render3d_st: mut Render3dState, b: []byte, srgb: bool) -> int {
   if len(b) < 148 or b[0] != 68 or b[1] != 68 or b[2] != 83 or b[3] != 32 { return 0 }
   if b[84] != 68 or b[85] != 88 or b[86] != 49 or b[87] != 48 { return 0 }      # "DX10"
   let h = dds_u32(b, 12)
diff --git a/packages/ludic.render3d/vkmem_report.ludic b/packages/ludic.render3d/vkmem_report.ludic
new file mode 100644
index 00000000..b8688f59
--- /dev/null
+++ b/packages/ludic.render3d/vkmem_report.ludic
@@ -0,0 +1,110 @@
+# vkmem_report.ludic — where the GPU memory is, by owner (R3D_VKMEM=<frame>, printed once at that frame).
+# Every allocation carries the owner its maker was wrapped in (gvk_tag); a block's unused room is
+# counted apart, since it is memory the driver holds for us whoever it will be given to.
+
+const VKM_OTHER: int = 0
+const VKM_MODEL: int = 1
+const VKM_TERRAIN: int = 2
+const VKM_SCATTER: int = 3
+const VKM_GRASS: int = 4
+const VKM_SHADOW: int = 5
+const VKM_TARGET: int = 6
+const VKM_SKY: int = 7
+const VKM_WATER: int = 8
+const VKM_TEXTURE: int = 9
+const VKM_FRAME: int = 10
+const VKM_IMPOSTOR: int = 11
+const VKM_N: int = 12
+
+function vkmem_tick(render3d_st: mut Render3dState) -> void {
+  if render3d_st.vkmem_at == 0 {
+    render3d_st.vkmem_at = -1
+    if r3d_env_has(render3d_st, "R3D_VKMEM") { render3d_st.vkmem_at = Text.to_int(r3d_env(render3d_st, "R3D_VKMEM")) }
+  }
+  if render3d_st.vkmem_at > 0 and render3d_st.r3d_test_frame == render3d_st.vkmem_at { vkmem_report(render3d_st) }
+}
+
+@alloc_ok("a report printed once, under R3D_VKMEM")
+function vkmem_report(render3d_st: Render3dState) -> void {
+  if render3d_st.gvk_al_tag == null { return }
+  let img = words(VKM_N);  let buf = words(VKM_N);  let host = words(VKM_N);  let cnt = words(VKM_N)
+  for k in 0 .. VKM_N { img[k] = 0;  buf[k] = 0;  host[k] = 0;  cnt[k] = 0 }
+  var used = 0
+  var own = 0
+  for a in 1 .. len(render3d_st.gvk_al_len) {
+    let n = render3d_st.gvk_al_len[a]
+    if n <= 0 { continue }
+    let t = render3d_st.gvk_al_tag[a]
+    let who = Math.min(t / 4, VKM_N - 1)
+    if (t & 1) != 0 { host[who] += n } else if (t & 2) != 0 { img[who] += n } else { buf[who] += n }
+    cnt[who] += 1
+    used += n
+    if render3d_st.gvk_al_blk[a] < 0 { own += n }
+  }
+  var blocks = 0
+  for b in 0 .. len(render3d_st.gvk_blk_size) { blocks += render3d_st.gvk_blk_size[b] }
+  vkmem_say_head(used, blocks + own, blocks + own - used)
+  for k in 0 .. VKM_N { if cnt[k] > 0 { vkmem_say_row(vkmem_name(k), img[k], buf[k], host[k], cnt[k]) } }
+  vkmem_big(render3d_st)
+  vkmem_cpu(render3d_st)
+}
+
+# the largest images, with their owner, size and format
+@alloc_ok("a report printed once, under R3D_VKMEM")
+function vkmem_big(render3d_st: Render3dState) -> void {
+  let n = len(render3d_st.gvk_tex_mem)
+  let done = words(n)
+  for i in 0 .. n { done[i] = 0 }
+  for r in 0 .. 25 {
+    var best = -1
+    var bn = 0
+    for i in 1 .. n {
+      let a = int(render3d_st.gvk_tex_mem[i])
+      if done[i] != 0 or a <= 0 or a >= len(render3d_st.gvk_al_len) { continue }
+      if render3d_st.gvk_al_len[a] > bn { bn = render3d_st.gvk_al_len[a];  best = i }
+    }
+    if best < 0 { return }
+    done[best] = 1
+    let a = int(render3d_st.gvk_tex_mem[best])
+    vkmem_say_img(vkmem_name(render3d_st.gvk_al_tag[a] / 4), bn, render3d_st.gvk_tex_dims_w[best], render3d_st.gvk_tex_dims_h[best], render3d_st.gvk_tex_layers[best], render3d_st.gvk_tex_levels[best], render3d_st.gvk_tex_vkfmt[best])
+  }
+}
+
+function vkmem_name(k: int) -> string {
+  if k == VKM_MODEL { return "models (gltf_load)" }
+  if k == VKM_TERRAIN { return "terrain" }
+  if k == VKM_SCATTER { return "scatter + streams" }
+  if k == VKM_GRASS { return "grass" }
+  if k == VKM_SHADOW { return "shadow maps" }
+  if k == VKM_TARGET { return "frame targets" }
+  if k == VKM_SKY { return "sky" }
+  if k == VKM_WATER { return "water" }
+  if k == VKM_TEXTURE { return "textures (game)" }
+  if k == VKM_FRAME { return "made in a frame" }
+  if k == VKM_IMPOSTOR { return "impostor atlases" }
+  return "other"
+}
+function vkmem_mb(n: int) -> int { return n / 1048576 }
+function vkmem_say_head(used: int, held: int, slack: int) -> void { print(`vkmem: {vkmem_mb(used)} MB in use, {vkmem_mb(held)} MB held from the driver, {vkmem_mb(slack)} MB unused room in blocks`) }
+function vkmem_say_row(name: string, img: int, buf: int, host: int, n: int) -> void { print(`vkmem:   {name}: images {vkmem_mb(img)} MB, device buffers {vkmem_mb(buf)} MB, host buffers {vkmem_mb(host)} MB ({n} allocations)`) }
+function vkmem_say_img(name: string, n: int, w: int, h: int, layers: int, levels: int, fmt: int) -> void { print(`vkmem:   image {n / 1024} KB  {w}x{h}x{layers} mips {levels} vkformat {fmt}  {name}`) }
+
+# the renderer's own big arrays on the CPU heap
+function vkmem_cpu(render3d_st: Render3dState) -> void {
+  var lay = 0
+  var cap = 0
+  for i in 0 .. len(render3d_st.sc_layers) {
+    let l = render3d_st.sc_layers[i]
+    lay += vkmem_fl(l.inst) + vkmem_fl(l.scratch) + vkmem_fl(l.gsorted) + vkmem_fl(l.vis)
+    cap += l.cap
+  }
+  var str = 0
+  if render3d_st.stream_all != null { for i in 0 .. len(render3d_st.stream_all) { str += len(render3d_st.stream_all[i].arena) * 4 } }
+  let ter = vkmem_fl(render3d_st.ter_heights) + TERRAIN_RES * TERRAIN_RES * 3
+  vkmem_say_cpu(len(render3d_st.sc_layers), cap, lay, str, ter, vkmem_fl(render3d_st.wb_cells))
+}
+function vkmem_fl(f: floats) -> int {
+  if f == null { return 0 }
+  return len(f) * 4
+}
+function vkmem_say_cpu(n: int, cap: int, lay: int, str: int, ter: int, water: int) -> void { print(`vkmem: cpu: {n} scatter layers (cap {cap} instances) {vkmem_mb(lay)} MB, stream arenas {vkmem_mb(str)} MB, terrain copies {vkmem_mb(ter)} MB, water cells {vkmem_mb(water)} MB`) }
diff --git a/packages/ludic.render3d/water.ludic b/packages/ludic.render3d/water.ludic
index a078ab2b..4892cac7 100644
--- a/packages/ludic.render3d/water.ludic
+++ b/packages/ludic.render3d/water.ludic
@@ -294,7 +294,14 @@ function water_body_add(render3d_st: mut Render3dState, level: float, cx: float,
 }
 # one reflecting plane: what this function always meant, without a new mesh and program
 # every time it is called
+# the GPU memory it makes is counted as VKM_WATER (R3D_VKMEM)
 function water_init(render3d_st: mut Render3dState, level: float, cx: float, cz: float, ex: float, ez: float) -> void {
+  let was = render3d_st.gvk_tag
+  render3d_st.gvk_tag = VKM_WATER
+  water_init__t(render3d_st, level, cx, cz, ex, ez)
+  render3d_st.gvk_tag = was
+}
+function water_init__t(render3d_st: mut Render3dState, level: float, cx: float, cz: float, ex: float, ez: float) -> void {
   water_bodies_clear(render3d_st)
   water_body_add(render3d_st, level, cx, cz, ex, ez, true)
 }