2026-07-15T09:29:45.734111 image/svg+xml Matplotlib v3.10.8, https://matplotlib.org/ One transformer block, op by op O L M o 2   o r d e r i n g     R M S N o r m   a f t e r   e a c h   s u b l a y e r ,   i n s i d e   t h e   r e s i d u a l .           = 5 1 2       = 8       = 6 4       = 2 5 6       = 1 4 0 8 C H h T h d f f attention sublayer i n p u t         z B T C ( , , ) residual rail m a t m u l     : 3 W C C q k v ( , , 3 )     s p l i t   i n t o   , , B T C q k v q k v R M S N o r m q R M S N o r m k s p l i t   h e a d s   ( = 8 ) H s p l i t   h e a d s   ( = 8 ) H s p l i t   h e a d s   ( = 8 ) H RoPE RoPE θ = 5 1 0 5 m a t m u l     = 1 / S q k h d ( , , , ) B H T T causal mask softmax over keys m a t m u l     = y A v ( , , , ) B H T h d merge heads ( , , ) B T C m a t m u l     : W C C p r o j R M S N o r m a t t n ◄ OLMo2: norm on the sublayer OUTPUT, not on its input + z 0 SwiGLU sublayer m a t m u l     : W C h 1 f f m a t m u l     : W C h 3 f f h f f = 1 4 0 8 SiLU ⊙ elementwise gate m a t m u l     : W h C 2 f f R M S N o r m f f ◄ norm after the sublayer, again + o u t p u t           o n e   f u l l     d o n e z f 0 0 l w e i g h t   ×   a c t i v a t i o n   m a t m u l     7   l o g i c a l   (   f u s e s   , , ) ;   c r o s s b a r - m a p p a b l e   o n   a n a l o g   h a r d w a r e W W W W q k v q k v a c t i v a t i o n   ×   a c t i v a t i o n   m a t m u l     2   (   a n d   ) ;   c o m p u t e d   o n   t h e   f l y :   t h e   n o n - c r o s s b a r   p a r t   o f   a t t e n t i o n q k A v RMSNorm (learned gain) elementwise / reshape N o   b i a s e s   a n y w h e r e   i n   t h e   n e t w o r k .     T h e   1 /   s c a l e   i s   f o l d e d   i n t o   ;   m a s k   a n d   s o f t m a x   r u n   a l o n g   t h e   k e y   a x i s . h S d h C C f f = 1 4 0 8 8 / 3 ,   r o u n d e d   u p   t o   a   m u l t i p l e   o f   6 4 .     Q K - n o r m   a c t s   o n   t h e   f u l l   w i d t h   ,   b e f o r e   t h e   h e a d   s p l i t . T h e   b o x e d   p i p e l i n e ,   i n p u t     t o   o u t p u t   ,   i s   e x a c t l y     o n   t h e   c o m p a n i o n   p a g e ;   t h e   s t a t e     l i v e s   o n   t h e   r e s i d u a l   r a i l . z z f z 0 0 l l