🔒 Plain mutex
👓✍️ Read-Write lock
✅ Release all
↺ Reset
reads served:
0
· writes:
0
mode:
read-write lock
readers inside:
0
· writer:
none
· waiting:
0
🚪 room — inside the lock
📄
Shared document
v3
nobody inside
⏳ waiting queue
nobody waiting
🎟 tray — click an actor to request the lock
⚠️ Upgrade R1→W
Two doors, one room
Click
👓 R1
, then
👓 R2
and
👓 R3
— see how many fit inside.
▸
Reading doesn't change the page, so readers never clash — only a
writer
needs the room to itself.